What's wrong with me?

I wake up everyday and immediately feel sick, dizzy, and cold. I have to stumble out of my house and I'm unsure whether or not I'll make it to the bus stop without passing out. I just recently started getting my pulse and blood pressure checked when I get to school. I don't remember my blood pressure but it's been low the entire course of this. Friday my pulse was at 117 Monday at 114 and today it was crazy this morning that everything was blurry but I laid on the bus and didn't move or check my phone or anything so when I got to school it was at 98. I was taken in an ambulance from my school to the ER. My doctors said I was dehydrated so I fixed that and now drink the amount they requested. It's been like this for about a year now. Can anybody help me? My parents also think I'm hypoglycemic.