Strange pain in head/under arm

I've had this slightly odd throbbing/pulsating/almost stabbing pain that seems to come and go.  It's on the right side of my head about 2" or above and a bit behind my ear, and it's in one fairly-concentrated location.  Simultaneous to the pulsating pain in my head, I have another pulsating/throbbing pain under my right arm, and again, it's in one concentrated location.  It seems to come and go randomly, some days it'll happen a lot, and others not at all.  The weird thing is it seems as if the pains are no-doubt related, as they come and go exactly the same time, and throb in sync.  It's been an off-and-on annoying issue for a while now (months), and I thought nothing of it.  At times it's more painful than others and lasts longer.  I just want to make sure it's nothing more than stress.  I'm 28 and fairly healthy, but I have had issues in the past w/ stress and also had major abdominal surgery a year ago (but no complications).  Anyone else experience this same sort of sensation?