I'm 13 and I have recently been feeling like I'm going to faint. It started out when I was 12 and I went to the sinus doctor and they ran a scope up my nose to check my adenoids and tissue. When they went out of the room to get some papers I fainted when I woke up I threw up all over my self. My mom thought it was just the fact that I can't be around medical stuff or it will freak me out and cause me to faint. Ever since then I thought it was just medical stuff but now it's gotten worse. Now it's everyday and my family is getting scared. I've had dehydration problem in the past. I have to take allergy shots every week too. There is also a blood pressure and diabetes thing that runs in the family. Idk if that my be the prob or not. I'm really really small for my age. I'm only 4 foot 10 and I weigh 73 pounds. Everyone else in my grade is 5+ feet and 100+ pounds. I've recently had a allergy shot test to make sure my shots are not too strong for me. When I do feel like I'm going to faint, but I don't faint, I feel nauseated afterwards. I also puke when I wake up from fainting. Is this from dehydration or something? Can someone tell me what this is? Is this something that needs to go to a specialists? Should I be worried?