Dizzy spells?

i'm 16, not pregnant and weigh 100 pounds.
sometimes when i stand up, and i haven't even been sitting for a long time, i bring all of the sudden really dizzy and form of black out approaching i am going to pass out.
i hold been to my doctor, and they said it be low blood pressure, so i have be adding extra brackish to everything i can, recently the dizziness is becoming more frequent and abundantly more intense.
so i don't really know what to do.
any ideas? quit the brackish, this can disturb your body salts (urea and electrolytes) and do bring down, yep o.k low b.p.but i would of expected at your age a series of bloods would be taken to get a picture of why this is scheduled.
definately go rear to doc, if you have already have tests asked to be referred to a cardiologist and you want some answers rotten him/her
Maybe you don't have ample iron in your blood. That's my problem (Iron Defficiency Anemia). Go to the lab for blood work, and verbs on your bottom eye lid. If there's white in at hand, you're anemic.