I get exactly the same thing, and it turned out to be sinus pressure! I am not congested and don't have any other symptoms; when I get a "sinus Headache", it is almost behind (and above) the ear where my glasses rest. I take sudafed and it gets much better. I send you good luck finding out what's causing your pain...
jan
From experince I had those same feelings, I went to see my eye dr and the glasses were to tight and then were loosen, and I was sufferening from an inner ear infection from the pressure.
did you get new glasses, Allergies. is there a welt or cyst behind your ear? either of these could do it. or it could be neuritis of a specific nerve in that region.