I'm devastated, I got bad grades in my exams, and I'm so sad + my friends got high grades and some of them got good grades + my crush got very high marks
I'm devastated, How do I get past this?

Do better next time or ask the teacher (s) if you can do something extra to increase your current marks.
Opinion
4Opinion
How about you change or study habits or maybe even try to study in the first place?
Punch the teachers
Study better/harder
Just work harder
Superb Opinion