I am 15 and ever since I was 9 something weird began happening to me. At times If I sneeze, pick up a heavy object, turn my head moderately fast, or even just looking to the side, and some other things, I get this horrible sharp pain in the back left of my head. Im fairly sure it's always in about the same spot. The pain is worst right away then slowly dulls away and can take up to 20 seconds till its gone. The best way I can describe the pain, is that it feels like a blood vessel is literally bursting in my head. Sometimes I even cringe and my knees buckle. I would love to know the cause, what this is, and any possible cure.