Do you have some kinda permenant virus
Heh, j/k.
I swear I have no idea what's wrong, but please, go to your real doctor - it could be something serious.
The only thing I could possibly give you advice on is the fainting problem.
Normally I feel faint if something happens and my heartbeat goes all quick und stuff, then it goes down v.fast, for example performing on a stage and then coming straight off.
It doesn't help if I haven't eaten or drank something energizing beforehand.
This could be why you feel like you need to eat/drink more.
Tea is a god for improving energy and concentration levels, I try to make sure I drink a mug in the morning.
Try to have something for breakfast, even if it's just a nibble of toast.
Also, water can sometimes help with headaches.
Oh yeah, and if you ever feel like you're going to faint, then tell the nearest person to you and take deep breaths. The moment you start to see black spots then you should get into the recovery position, unless you're unconcious.
(can you tell I've fainted before and have low blood pressure?
)