Unqualified opinion from a retired pilot. However, some of you will have seen multiple posts by me on classical migraine. I've seen what it can do.
The patterns do sound like something is going into spasm because of a perceived threat. I hypothesize that this mechanism can misidentify problems and be very counter-productive.
Bear in mind that blood vessels have very complex structure and react in the case of trauma. It is odd how sometimes the relief of stress seems causal. "Sunday migraine," is the equivalent to that I'd imagine.
What to do? Well, breaking the cycle is vital, and I think that in the case of counter-productive spasms, there is a valid case for the TEMPORARY USE of benzodiasapines.
I shout temporary, because of the dangers of using this amazing drug. For me, it was rage, in others it has been total addiction with a slew of unpleasant symptoms. However, the short term use under supervision may be very telling.
If your GP would prescribe sufficient Valium for such a test, then, at least in some people, they may find that it unlocks the root cause of the overall pain. Taking a modest amount and then really trying to relax the affected area might just bring results. If it does, then the next astonishing fact seems fairly consistent in many cases: Once the problem is identified, it's almost as if the circuits causing the problem know the game is up. The need for more Valium diminishes or even goes altogether. Having some nearby is like a Linus Blanket. The comfort of knowing it's there if you need it.