About once a month I get EXTREME flank pain (completely debilitating). It seems to occur when I take a hot shower. Also, ibuprofen seems to set it off. I've had a catscan and blood tests and everything appears to be normal. What could possibly be going on?
Since all your test are normal, I would wonder if the pain is referred pain(possible from disc, possible arthritis). It is good that your scan and blood test are normal. Sorry I couldn't help.