I know how you feel, I still feel like that in college and hate sitting in front of people. If it's any consolation, I've never seen anyone over the age of like 10 get sick in public. Also, I think people get better at understanding how they feel as they get older and get more embarrassed by being sick in public. That's why you really rarely see older people get sick. I just remind myself of that every time I get panicky and it helps calm me down. You also might be able to talk to your counselor and get disability accommodations so you can always sit in the back.