Should I seek professional help? Many questions-please help!

ITS REALLY LONG-JUST SKIM IT UNLESS YOURE REALLY REALLY BORED.

This is my first ever post on here, and I'm not totally clear on how all of this works but I really need to share what I'm dealing with and get advice from people who know what they're talking about!

I'm not really sure where to start... I guess just with my questions.
I will share my symptoms and some history, but here are my questions:
-- Based on the info I give, do you think I should be getting help from a professional, like a therapist?
-- I know there are different types of anxiety, so what (if any) type would you guess I have? Or am Ijust freaking out over nothing...
-- What are the top things that have helped you deal with anxiety or had the best results for you?

Okay well, I am currently 18 and about to graduate highschool (2 and a half weeks!) And I'm finally feeling more ready to talk about anxiety.

Probably in 7th or 8th grade is when my social anxiety symptoms first appeared, and got a lot worse in 9th grade and on. Before that time I wasn't all that shy--I competed in speech and poetry competitions, and was an outgoing kid. In junior high I started to have some self esteem issues, just more insecure about myself and my appearance. You should know that I've gone to a small private christian school my whole life, so there were at this time probably 18 kids in my whole grade so we had all of our classes together and there were some strong personalities in there who didn't like me, so I struggled with feeling insecure, alone, minorly bullied, etc. I started to avoid social situations because I felt like people wouldn't like me, I wouldn't fit in, and stuff like that. My parents would force me to come to neighborhood cookouts and my older brother would just go right in and hang out with the other kids, but I was so self-consious and scared that I couldn't do it. other Parents would come up to me and be like "looks like all the kids are hanging out over there by the ping pong table" hinting that I should go over but Icouldnt and it made me even more embarrased. At youth group events I wouldn't join in any sport or activity bc I was scared of looking dumb by not being good enough. I would come up with excuses to get picked up early or not go at all.
in 9th grade, a lot of kids transfered to public school (including my two best friends) and some new people transferred in, so my class size reduced to about 10 , all of whom i was very uncomfortable with. This year was really really bad for me, I'll try to keep it short. Everyone was very sports oriented (im into music, books, and non-school sports like rock climbing) so I didnt fit in, even though its not like i wasnt fit and healthy,and I was very quiet--my class thought I was weird and would talk about me even though I could hear them. With that small of a class you would think that it would be impossible to be excluded, but thats not the case. I had very dark feelings, my parents were worried but were busy with my siblings (learning disorder and getting into colleges) I statred to experience syptoms like extreme blushing if someone even looked at me, lots of negative thoughts, shakiness and shortness of breath when I had to work with a partner or go to gym bc I hated when people paid attention to me, which wasn't often bc it was usually like i didnt exist to my class. I began to self harm and only pulled through thanks to a great friend I made in the grade above me. once the summer came and i got out of the negative environment, drama, and not fitting in, I felt alot better emotionally and recovered some from that (basically by myself-my parents dont know about the self harm) but my parents notice the difference when im on a break from school.
10th grade was a little better-still really hard. no more self harming, but more anxiety symptoms. I avoided any social situation outside school at all costs. I didn't and still don't have any friends that I havent known my whole life or wasn't forced to know thanks to my tiny school. At this point, my class size was down to 8. I had thoughts all the time about being judged, low self esteem, occasional self-harm but not at all like before, fear of strangers, avoiding people and life in general... started to make a friend in my class though so that helped a lot, and the people who were making it a really hard time for me started to transfer one by one so that was also good. still was pretty much ignored though.
11th grade, my class was down to 6 people, I was so tired of being miserable and being excluded that i tired to be friendly with the people who really hurt me, and it was like they dont even realize how they affected me, which hurts. that year was kind of a blur... heavy homework load, [pressure, I am a perfectionist and I put a lot of pressure on myself so thats difficult but i cant help it. the other kids in my class are very judgemental and now in 12th grade, i know they kind of care about me, but they dont really understand me and they think i have no problems because i try so hard to be nice at school, bc if i say im having a rough time they just make a joke out of it. my symptoms have gotten way more severe, even just talking to two people, i will realize theyre focused on me and i will start to feel out of breath, my heart will pound (you can see it, like it moves my clothes it beats so hard.) and when I have to give even a tiny presentation, i shake uncontrollably and feel like i cant breathe-which i know everyone notices and makes it worse... and i mean literally, i will be 19 in 6 months and i get intimidated walking past a big group of 16 and 17 years olds, its so ridiculous.
Sorry this has gotten SO long, but one more thing
also at my school the seniors have to do a senior thesis project (25-30 page paper on a topic youve researched "all school year" and a 15 minute speech to other classes/teachers/headmaster/boardmembers/etc.). My speech is on Tuesday and for the past two weeks ive been sick to my stomach (sorry TMI but diarrhea) and I get hot flashes just thinking about it-especially since it includes a cross examination and i know my symptoms will be out of control. (advice for this??)

FINALLY i am taking a year off before college bc i dont know what i want to do and i need some time away from school to become myself again--- anyways there are these travel programs i want to do but when i watched the info vids they have a required social time with other volunteers and when i saw that i immediately got all hot and uncomfortable and turned off the video, throwing away the option. I dont want my fear to keep me from doing the things I want to do but im SO SO SO scared to tell my parents bc im worried they will just want to pray about it and go to meetings about it but i just want to see a therapist or get other help:/
Sorry this is soooo long and thank you so so much to anyone who took the time to read this--it was supposed to be shorter! I could use any advice you can give--either on the beginning question or how to talk to my parents, or anything like that, i just feel so alone in this right now and its getting harder to manage.

I really appreciate all responses-thanks(:

-- Based on the info I give, do you think I should be getting help from a professional, like a therapist?

Yes

-- I know there are different types of anxiety, so what (if any) type would you guess I have? Or am Ijust freaking out over nothing...

You seem not to be freaking out. The first line medicines that target anxiety are antidepressants, so there may not be a huge point of distinguishing SAD from GAD and so on..., at least not at the first moment.

-- What are the top things that have helped you deal with anxiety or had the best results for you?

Mindfullness
Therapy.
SSRIs(Medicine)
Not at a order of results, but at a order of measures I took.
I know mindfullness meditations arent real treatment, but they give you a more objective approach to life.
Therapy helps more with social kinds of anxiety.
And finally SSRIs stabilize your mood.