well im 15, and sometimes when im lying down on the couch and get up, [its not a quick motion] 15 seconds later i feel like im going to faint. my vision gets a little blurry, my vision gets kinda black but slowly goes back to normal, and i loose my balance. i feel like im actually going to faint one day. the feeling lasts anywhere from 15-40 seconds. i exercise daily, and all i drink is water, and cranberry juice. then someone said this is caused by a drop in blood pressure, and that i may even have low blood pressure. what causes this and how does this affect my body? also, they said anemia is a possibility, what is that? i know of nobody in my family who has this kind of problem, so i feel kinda lost. i plan on going to a see a doctor soon =/ thanks for the help i appreciate it