2009.4.1@dizzy

I am always dizzy and suddenly dizzy. I don't know why. In fact, I have finished my diet schedule on 21/3. ~~~~ and eat different kinds of foodsssss. I am dizzy when I am singing and practice in choir. sometime I am dizzy after drunk coffee. Oh my god !!! I need to join the choir to worship almost each Sunday. I can't sing smoothly. What should I do?