yeah i get that too... it just incapacitate me for like 10 minutes. Can't do shit and just have to relax. i can't even see straight cause of the pain and stuff.
happends a lot the next day i drink vodka. I never found out what it is, did cat scans and everything. just feel like you blood pressure is so high right? as if you heart is trying to pump too much blood up the arteries or something...

If you ever find out what it is let me know please... I still have attacks and it's a bitch!