For about the past six hours, I've had a sharp pain that somewhat comes and goes at the bar of my skull on the left side, plus an always present kind of mild headache. The part of my head that hurts (left base of skull), also is semi-tender to the touch, or rather it hurts to press or massage there. Any advice or thoughts on it would be greatly appreciated. It has happened before too. A few weeks ago, and a few months ago.