I feel like I'm just wired to suffer

[16M] I'm always stressed.. the smallest things.. the slightest cues, the smallest conflictsmake me stressed. It's been years.. many people have pointed it out, but I'm still not able to stop my excessive rumination. They tell me to just stop it or to not speak about it, but it doesn't help

Since the last year I've been preparing under a high pressure environment for jee.. which has 10× worsened my stress. Even when I try to take my mind off things, my body feels uncomfortable. My heart is racing most of the day and I feel breathless.

When I try to rest I feel like I'll get left behind in academics and fail my parents.. I am never able to relax. I don't fit in with anybody, I get mocked for being short and often times I have to say things multiple times in groups for anybody to even notice.

My mother has pretty bad mental health since 6 years, I just want to make her happy and do something.. everyday feels so heavy. I see her crying every week due to her personal struggles.

Studying for me is very stressful, even thinking about failing in JEE or some hard topics makes my breath shallow. I still push through and study for hours a day.. but it hurts. My mind often starts contemplating about outcomes. I feel so alone.