I am in the EXACT same boat! I started uni at the beginning of the year and started off perfectly fine. Well, it was always at the back of my mind but I got on with it and focused on meeting new people and having fun. Then after the beginning of my second semester, it came back with no warning. I have panic attacks at the thought of having to sit in a lecture for 2 hours in case I get sick and have recently started having them at home where I used to be perfectly fine.
I really hope you find a way through this. I have to disagree with transferring schools though. It's only a short term fix and will ultimately mean the emet has won. You were doing fine at the beginning of the year and you will get there again! Go and talk to your doctor and see what options there are.
Good luck!