I am a 43 year old white male, in decent physical condition. I work out in the gym 4-5 times a week for an hour each time. The other night I had a severe headache that felt like my entire brain was being stabbed, cold/hot sweats, felt like I was going to vomit, and had mild diarrhea. It lasted about five hours then stopped (took two excederine migrain pills), any idea what might have happened