I've Been Having Sharp Pain On The Left Side Of

I've been having sharp pain on the left side of the back of my head. They last 10seconds but keep occurring over & over. If have taken IB & excederin. It takes a lot of them away but never eliminated. I take the pills every 4 hours but long before that time passes, they return in force. I got a bad hacking chest cough on Friday and then this started on Friday. Also, I was on a cruise at the time to the western Caribbean. Any suggestions to stop this pain?