Is this from the wave you stuffed awhile back when you went fishing? Does the pain shoot down one side of your ass? I have the same. Happened while chipping 6" of ice on the driveway. Sciatica. PT had me doing stretches with my knees to my chest and laying on the floor with my feet and calves on the sofa. PT bent my straight leg back at the hip while I was laying on my back. I woulda hit him during that one if he was in range. In my condition I'm sure he weren't too skeered. He said to alternate heat and ice as well. Later CT scans showed degenerative arthritis of the spine. Too long in waders while duck hunting will bring tears to my eyes as will all day in a layout blind.
I'll bet humpin' and layin tile for a few decades hasn't done you any favors. Hope the doc gets to the bottom of it and you heal up soon. Constant back pain is no way to live.
