What's going on here???

I don't know what is wrong with me... for three weeks I've been having quickened heartbeats and for the past two days I haven't been able to breath or take deep breaths. Yesterday I went to the ER, if you know me you know I don't do hospitals, until 24 hours ago I never had to have my blood taken. It wasn't as bad as I imagined it would be so I guess that's a plus. But after being in a germ infested hospital for three hours they said they couldn't find anything wrong with me... yet I still feel horrible like a huge textbook is on my chest preventing me from breathing. Today in my living prophets class I couldn't even make it through the opening hymn I was so out of breath. Every time I watch the news someone new has died from swine flu, while I don't have the flu bug I somehow feel that I am next... :( I am freaking myself out... It may be anxiety attacks but I don't have anything to be anxious about and this anxiety attack is lasting almost a whopping 48 hours!!!! All you doctors who are reading this please diagnose me!