Can someone help relax me?

My anxiety is BAD. Today is supposed to be a super good day, because today at school all we're doibg is rockin out to music outside and stuff. ( I'm in junior high) but I'm so anxious that I feel really really nasty inside and idk how to calm down because I don't wanna throw up! I have Emitophobia. Can someone help please? I have add and ocd ans I'm already seeing a coucelor.