I haven't experienced this myself, but my ex boyfriend went through something similar to what you describe happening due to kidney stones. Every time the stone moved, the pain was visibly terrible. But I'm not sure if an x-ray is enough to detect smaller kidney stones, my ex had to have an ultrasound done as well and that's when we saw tiny, almost sand like stones that were causing so much pain.
If you have kidney stones ruled out by now, it might be your spleen that's causing the pain. It's not something that happens often, but spleen can get inflamed too. If that's the cause, CT will detect it.
Wish you all the best,
Thanks for your reply. My Urologist seems to be testing for Kidney Stones and that's why I had the CT Scan. I have had xrays and ultrasound of the urinary system but they said that kidney stones don't always show up on these tests. I have had suspected kidney stones about 10 years ago and I certainly remember the pain then and it's way above the discomfort i'm getting now. My flank areas and below my belly button feel constantly uncomfortable. I don't think it's my bowels as I have regular movements and always ok - never D or C.
Any more ideas anyone??