Dizziniess, plz help!??!

Dizziniess, plz help!??

Okay, I'm only twelve, but sometimes when I stand up I get dizzy and I have to lean against a wall to prevent myself from falling. I just started experiencing this a week ago and it hasn't gone away. I don't think its fatigue and I'm physically active, but I drink a lot of water so its not dehydration. (and I've told my parents about my problem already and they say its probably nothing). Also, lately I've been having to pee a lot (if that means anything). I eat a balanced meal and hardly have sweets and ice cream (I know its weird, but I don't like that stuff).

*****I don't want advice on going to the doctors.****
I want to no what may be wrong with me.

Thanks for helping!

3 days ago
It doesn't just happen after I watch TV though. I play tennis, fence, lacrosse, and squash and earlier this week was in a fencing competition (summer nationals) and all of a sudden I had to lean on my foil because I couldn't walk without falling over the world was spinning so much. Then also when I was walking just from my bedroom to the kitchen downstairs I had to lean against the wall and wait for my nausea to stop.

Also, I've been peeing more then usual if that has anything to do with it?

3 days ago
And I'm a girl

3 days ago
I've posted this like twice and people have suggested diabetes, I don't think its that because I know most of the symptoms (my best friend was diagnosed 6 months ago)

3 days ago
Also, I don't think I have heart murmur because I drink a bunch of caffeine (its my favorite :), actually its like midnight now and I'm bouncing off the walls, but tonight is the latest iv stayed up in a week, so its not because of fatigue.

You sure do have alot to say for a 12 year old...

Don't think it's asthma or a lung problems because you would get a gasping effect. I'm gonna take a longshot though, it sounds like a sort of heart murmur.

Maybe you drink caffeine or energy drinks, or even powerade drinks that have high levels of vitamins in them.

Maybe not... but what a heart murmur is, having had one myself, is when your heart skips a beat, or gets confused on when to beat. It results in a flutter feeling in the chest and a dizzy feeling in the head. It's often induced in a sensitive person by energy drinks or stimulants, also from over-hydration even from water.