I'm 23 generally fit and healthy, but for about 3 months have been getting dizzy after about 15 mins a aerobic class - sometimes hearing/vison distorts and i feel as though i'm going out of my head somehow and need to sit down for about 5 mins til it passes. This happens nearly every time I do a class.
Generally doesn't happen during my every day life. Others things I'm noticing are that i seem to sweat more than anyone else in the class and when I walk for any distance I also get sweaty though I'm fit and not overweight.
Whats wrong with me?