Hi Yankee,
Yep, you really do need to go back to the doctor and insist further tests are done.
The IBS diagnosis is a bit of a cop out, as it means that the doctor doesn't really know what the problem could be so they just lump it into the IBS arena and then give you tablets to help ease the pains, but not tackle the actual problem.
A good book on IBS, that helps you to identify the possible cause of your own particular symptoms and offer advice on how you can deal with it, is called "Irritable Bowel Solutions" by Dr John Hunter. (
Irritable Bowel Solutions: The essential guide to IBS, its causes and treatments: Amazon.co.uk: Dr John Hunter: Books) An interesting read and quick to get to the point, so you don't have to read 300 pages before you can start identifying things.
Pains in the lower back and coming down to the groin area could be numerous things, though it does sound similar to when I had a kidney stone (Is the pain in the kidney region?) as the kidney stone was sharp and scratched as it went down the tube towards the bladder and then became painful when it lodged in the tube just before getting into the bladder. Of course that's my experience, so you should get your doctor to check by doing urine tests for blood and blood tests for kidney function if (s)he believes it appropriate. That could also be possible as you indicate a calcium stone for yourself, and kidney stones are generally calcium based.
Not sure about your other symptoms, that may be related to the "IBS", though definitely get to the doctors and rule out things that are more serious.
All Love and Reiki Hugs
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