To begin, I should mention that I've suffered from migraines for several years, however, recently I've been experiencing very sharp pains intermittently from the left side of the back of my head, shooting forward to the back of my left eye.  These pains are random, in that they do not correspond with my migraines, (at least I don't think so.)  They generally last just a few seconds and I can feel the pain travel from the back to the front of my head.  It's kind of freaking me out.  Should I be concerned?  Should I see a doctor about this?  What might this be?