That's what you have to do-steadily explore your options and eliminate what you can.
Hard work with a sore head!
I'm having a bad time right now with pain where the neck joins the head, and also the shoulders. My joints tend to lock up a bit and the result is nerve irritation, which includes eye pain.
It was brought on by driving for nearly 3 hours a few days ago.
Have you had your cervical joints critically examined for spurs, narrowing, joints locked or out of alignment?