First of all, there is nothing wrong with excelling in one particular EC - which you have absolutely done with chess. I think that for now, the most important thing for you is to focus on your mental health. Counseling, possibly medical treatment, and trying to figure out what would make you happier. I know you say that you are introverted, but would more fulfilling social interaction make you happier, do you think?
This summer, can you do another program to help you explore whether you want physics or engineering? Even though you don’t have to decide before you apply to college, it may help to focus your college search if you’ve figured out which you want.
Academically, you’re going to be fine, even if you don’t go to a tippy-top school for undergrad. Right now, focus on your mental health, and on exploring to figure out whether you want engineering or physics, so that you can focus your college search to fit your intended field of study.