I am a 24 year old female. I never got headaches until June 25th of this year. That one was really bad. I was in bed all day. Since then, I have been getting headaches multiple times a week, sometimes daily. Along with these headaches, I get quite nauseated, have diarrhea, and am Very tired. I also get really bad hot flushes that sometimes make me feel like I will faint. No fever though, and no sweating. When the hot flushes happen, they last for hours on end. What could be causing this?