Hello. I´m 16 and I have been struggling with a problem in my head for the past 3/4 days. Every time I exercise, my head starts hurting, and it is not a common ache. It does not allow me to continue to do whatever I am doing at that moment. It is a sharp pain in the left side of the back of my head and it hurts whenever my heart beats. I have already been to a doctor but he just told me to take some antibiothics with caffeine. Does somebody have a possible explanation?? Thanks.