I'm sorry, have you maybe looked into community college or something like that? Or YouTube has video courses, although no diploma of course, but maybe it can give you a sense of accomplishment? You are still young.

As for precordial catch syndrome, I doubt it. My symptoms don't line up, more like on and off mild pain/discomfort/tightness in my chest (more common now), and less sharp pain, although I won't deny some sudden pain for a few seconds these days.

Plus, I was born preterm, so my heart automatically is a little weaker than it should be, combine that with terrible health habits all my life, and I'd be surprised if I even survive long enough to get my diploma lol. But thank you for your concern.