try a chiropractor. you probably have a really tight muscle impinging the greater occipital nerve and c1 is out of place.
I'd work this out with allopathic physicians before moving on to alternative medicine...
HEY!
You momos need to stop hating on Chiros, most especially if you have NEVER even been to one!
Before I got out of the Army, I started suffering debilitating headaches, emanating from the back of my head. Flight Surgeons never X-rayed me, just gave me some muscle relaxers, said it stemmed from having my head bent down watching the instruments so much and "having my head on a swivel", said it was a common malady with Airmen.
Civilian Docs, same thing, just told me to take NSAIDS, often prescribing some mild painkillers, but inevitably I would get a killer headache 1-2 times a week for ~20 years.
(Ex)Wife started seeing a Chiro for a disabling misaligned vertebra, fixed her right up on the first visit.
Meanwhile, she mentioned my headaches. He had her tell me to come in, let him check me out, and if he could not fix me, he would not charge me anything.
I went, he did X-rays, my neck was 100% misaligned! (Curved far forward where it should be curved slightly back).
It took 6 weeks and I was miserable with a stiff neck, but after he got my neck re-aligned (with X-ray proof of such), the headaches stopped.
Still have not had even one of those headaches since! (Almost 20 years, now), & I have probably had only 5-6 "regular headaches" since.
But that's not all the story, I had been having some horrible constipation (like 1-2 BMs a week!), his X-rays showed misalignment in the vertebra surrounding the nerves that control the bowels, he worked on that also, been regular ever since!
You see, your spine, and the nerves from the spine, play an integral part in how your various limbs, organs, etc. work.
Spinal misalignment causes many, many problems which can be taken care of with Chiropractic therapy (proper spinal alignment).
They can also (usually) be taken care of with Traditional medicines, therapies, & surgeries, but why go to the trouble & expense when a Chiropractor can fix these things inexpensively, usually in the afternoons so you don't even have to miss work!
In other words, don't knock it until you try it!
I'm lucky to have found a good Chiropractor here, though I don't see him often enough!