My first guess, is to see a chiropractor.

If your spine is not properly aligned, you can have similar things happen, and most pain killers wont help the pain go away much at all.

I know alot of people think that chiro's are quacks or whatever, but if you cant find any other answer, Id look/ask around, find a good reputable chiro, and give them a visit.

Lord knows I feel 100x better when my back is out and I get back from the chiro.