My bmi is 18.5 am i over weight if i exercise 3 hours a day i am 13 and 5'4?

18.5 is a very very low bmi. Actually the heathy range for bmi is 18-25 so i assume you are very thin. Don't worry about being over weight because you are FAR FROM IT! =D good job! keep on eating healthy, and more importantly in MODERATION!