What is the cause?

Okay, when i was about 13 i started keeping sharp pains at the bottom of my head where my neck was. It would feel like someone was shoving a needle in my head and i felt as though i could like almost feel the blood rushing and it would get really hot. It was so intense I would just collapse and start crying and then a few minutes later i would be fine. It would happen every month or two. Then it started happening more often. And now, its happening on my right and left temple areas too.

I am 17 now. Do you have any ideas as to what could be the cause of this?

Thanks