I'm 99% sure you and I are experiencing the same problem. I have a few quick questions to be sure though. These are all things that I've been experiencing and have noticed.
-is the pain sharper in the moments when you first wake up or first activate the muscle after a long rest (eg. after sitting for a few hours)?
-Does it appear to go away after some light movement/mobility type things (swinging your leg etc that sort of thing).
-Does it reappear if you further the ROM for at least the first minute? Mine goes away for walking but returns for the first minute of a run and then persists a bit all the way through.
-Is it a dull pain in general?
-Does it hurt to bike? (i am much more ok with biking at the moment than running, perhaps because its not being used as much?)
Maybe this will help:
My pain is up towards the brevis/longus and tract areas. Right up tucked under my hip almost. However it has recently extended some into my gluts as well (which has prompted me to stop running for the time being and figure this out).
If it sounds like we are having the same issue I'll post any info I come across here. If not I'll start another thread.
Some initial thoughts though are just that we may have overworked the muscle and need to let it rest/recover for a good while. I let mine sit for a full week (well I did still lift but no legs and not much that would activate it outside of walking around) and the pain did go away. It came back however after a day or two of running again (maybe more time?).