Your life is far from over. People run into unexpected twists and turns all through their life, be lucky you still have your health.
Find positive things to surround yourself with and better ideas will come on what you should do with your life.
I have no advice on if you can still get into grad school or not, but you never said why it just clicked you wanted to be a professor in physics.
If you can't do physics, then why do you crave it? In your mind what makes you want it so bad?
If doing physics stresses you out and you just do "okay" in these subjects do you really still enjoy it?
Usually but not always, if you enjoy something you find you do excel in it. If i dislike a subject its usually only because I don't do well in it. But that's just me.