I don't see this as an ER situation.
For me, I've learned to be really honest with myself when I get odd sensations. by that I mean, what kind of stresses have I been under? How is my sleeping? How is my diet? Am I getting enough exercise? Am I engaging in reactive behaviors that is keeping my body symptomatic? I basically make me take responsibility for myself with regard to how I am feeling. If I can, honestly, see that stress or my actions are causing X, I deal with it without seeing a doctor.
If I can readily tell that I am ill or something is wrong, then I go to my doctor. I never go running off to the ER. I figure if I am asking if it is an ER situation, it really can't be. ER situations ARE as described, emergencies.
So, if you are THAT concerned, if you think this is an emergency, then go. If you think, "wow, these head symptoms have lasted too long and I know I haven't been living anxiously and/or feeding my anxiety", then have your doctor take a look. If you know you are stressed or been obsessing, then, imo, you should treat it as a manifestation of stress/anxiety.
Ultimately, it is your decision.