(((((((Hugs))))))))
I'm sorry you're feeling so anxious

It's no fun at all to be feeling this way, especially when you've got things that you have to do.
I hear you on the homework thing. I've got midterms and assignments ALL over the place, and anxiety certainly makes it harder to get anything accomplished.
You said that you started to break down last night but stopped yourself? Do you think that you would be able to let yourself have a breakdown so to speak? I find that if i'm constantly reprimanding myself for having all these feelings it only makes things worse. Sometimes, if you can give yourself permission to feel overwhelmed, and you can get some of it out.. it actually really helps.
Now i'm one to speak as I seem to have a certain difficulty with that, but i think the key is to just try and not beat yourself up about how you're feeling. If you are able to acknowledge these feelings, admit to yourself that yes, you feel like %#@&#!.. but not dwell on it.. just recognize it, that can help too.
Sorry if i'm not making any sense.
As for your friend, well worrying about him isn't really going to do anything. Maybe he just needs a little space right now? There could be lots of reasons for why you haven't heard from him ... if this continues and you don't hear from him in a couple days, then that could be more grounds to allow yourself to worry.
Hope you're feeling better soon...
Jacq