Anxiety in its various forms can be debilitating and is serious, more serious than many know.
At times we have to put in place ideas and actions to help us out, like you did in trying to be in your friends class. So well done in trying.
If it doesnt work out the way you planned, thats sadly how life works. We have to find other ways.
please google the following and read the first post.
Beyondblue Topic anxiety, how I eliminated it
Beyondblue Topic never ever give up
I hope that helps.
Thanks for coming here