You are more than your grades.
You are more than the bitchy remark that girl at the back of your class made.
You are more than the red marks on your test.
Things will be okay. Take a deep breath. If you're in high school, I know it sucks. But it's what you've got to do. If you're in university, take it in. You've made it this far. Try to enjoy the learning even though it's easy for it to get lost in all the stress.
There is so much to all of you. So so so much more to you than how well you're doing in school, and how well you get along with the people in your class or program.
I know it's hard to see. And I promise I'm not just saying that. I don't see very much more in myself then my grades and my weight. But there isn't a single person that I see purely through their grades. Please remember that your health is more important than school. And this will always always be true.