Need help with a mental/medical issue.?

I have a problem that I've had my entire life. It started when I lost my first tooth. When I did and I saw the blood I ped out and fell into shock. After being on a bed with my legs above my head laying down, I woke up and puked a lot. Now, this was 3-5 years old. I am now 16, and I still have this issue. Not to teeth though. Every time I've had a shot, That happened, except I didn't p out. I would go into shock, go extremely pale with nothing but a feeling of cold. I lost all of the feeling in my arms and legs and I could barely move or breathe. Now Maybe 10-15 minutes afterwards I calmed down and begun to get feeling back into my limbs which really hurt. Overall this has happened many times throughout my life, and I don't like it, I don't know what causes it. I'm not scared of pain, I'm not scared of needles, hell even one time I was prescribed numbing medicine to put on my gums and the first time I put it on I freaked out. Now, In the next 2 weeks I need to get a cavity filled, and when the dentist told me that I had to get a shot in my gums with novacane (it happened today) Just that THOUGHT made me go into shock. I freaked out and they had to get 3 other people to come in because the dentist didn't know what to do. I'm curious to know if anyone else here has this problem, knows someone with the problem, or has heard of it and knows any way to get rid of this un-preventable bodily reaction I have.