Often Dizzy
Hi!
This is perfectly normal. It is called a close faint, and happens because your blood pressure falls a bit when you stand up too quickly. The drop in pressure makes you become dizzy, it can disturb your vision can even faint. This makes your body lie down a bit so the blood pressure rises so blood us pumped to your head again. You do a few things to improve things, though. Drink enough during the day, don't stand up in a rush, tighten your leg muscles before you stand up and sit down quickly if you know feel those symptoms you describe coming on, so you don't faint. Often it improves when you are done growing and become an adult.
On the other hand, if you often have dizziness trouble even when you haven't just stood up, you should get yourself examined by a doctor. The Nurse you have at school can help you find out which GP is yours, and help you book an appointment. Going to the doctor when you're under 16 is free, so an examination will cost you nothing.
All the best,
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