noob questions

hi,
1.how can i be sure i have the BP disorder ? i mean, i have read the '' You know your bipolar when... '' topic, and everything seems to be normal. and by ''normal'' i mean familiar

2.it is possible/normal that my mood change to 180 degrees even twice per day ?

3.it's normal to miss my depression ? and when i have it, to hate myself because i wanted it back

4.also, sometimes i can't stop laughing (especially at school when a teacher makes a typo - but not only) i hate my brain so much in these moments, but still i feel good dafuq brain?

PS: i'm sorry for not-my-perfect-english
PS2: please, give me short answers. i can't read wall of text

Only a Dr can diagnose you. That is for your health. Do you really want people with mental illnesses diagnosing you or a doctor that has gone through med school for 15 years?

I agree with vegasguy, but will add the answer to 2 is yes in my case.