Fear of everything going wrong(health)

I'm 25 years old. When I was a kid I was exposed constantly to family dramas and fights between my parents, sometimes violent. Growing up I developed a strong character, always calm and honest with myself, a strong physical constitution.

Thanks to this I've always been healthy and fully recovered from 2 car crashes, 3 neck vertebrae disks fractures, internal throat bleeding due to glass splinter in food losing 1.3 liter of blood, multiple head physical traumas from childhood, almost losing a testicle when little falling from a tree, bipolar episodes 3 years ago when my father died and more.

For the past 4 months or so up until now, I feel like something's wrong inside. At start I thought it was something casual as always, but it doesn't go away. Especially when I try to fall asleep, I can feel muscle spasms a lot more and sometimes I wake up due to my own body jerking, shaking the whole bed, waking up scared. Also when in bed sometimes I feel like my heart stops beating and I'm about to pass out, and that's where anxiety starts eating me.

I'm saving money for a full blood check-up which is really expensive where I live. I also live alone and have to pay for a lot of things and saving money isn't easy, not on the best of terms with family so asking them for help is not an option.

My mother says it's all in my head and that I should switch to a healthier lifestyle and I'll feel better but I know it's more than that. I've never felt this way, even in the worst conditions I've ever been in the past, this is different.

I smoke a pack of cigarettes daily, drink lots of beer during weekends with friends which is actually the only time I'm not anxious. I don't do drugs, I also have a pretty chaotic sleep pattern and I workout 4 times a week.

I'm starting to be scared, afraid and feeling weak. I don't feel like myself anymore.

How do I deal with this?

Ofc we can't say that it's absolutely nothing, but nothing you've said can't be also explained by anxiety and poor habits, like smoking and chaotic sleep. Jerking when falling asleep is common- irritating, but a known phenomenon. I've gone thru bouts of my heart racing when trying to compose myself for sleep. I've felt weak; shaky; oodles of other things that could be either something terrible. Or anxiety. Which I have in spades.

Thank you for the reply. These past 4 days I've automatically come to the conclusion that being afraid is useless and that this is just another phase or transaction from my old self to the new reality I'm in.

Maybe the way I feel is all caused by me being unable to move forward and find a real thing to believe in.. there were times I had to hold on to something(chair, table) because I felt like I was about to fall down and my brain about to shut down, it once happened in front of my mother too and I felt pretty pathetic in that moment. It's funny how the subconscious adapts and gives answers in time..