It's really interesting to hear the link betwenn HMS and stomach problems. I've been on a very strict gluten free diet for many years now following the suggestion from my gyneacologist that I may have coeliac disease. my numerous symtoms at the time cleared up and I'd never felt so good. I particualary noticed the improvement in my back pain, general joint pain and migraines and cluster headaches.
For a number of reasons I never had the tests for Coeliac other than the blood teat which came back as negative. However I knew that a positive result for Coeliac can
show a negative blood test.
It wasn't until my mum was diagnosied with Coeliac disease several years later that I then had the biopsies done however my results were still negative. I had been on a gluten challange before the test ensuring that I had high levels of gluten in my diet - eating all the bread and cake I'd only dreamed of eating for years

It didn't make me happy though, I felt so ill and had to be off work.
The diagnosis i was given was IBS with gluten sensitivity. I would argue though that as long as I stay on a gluten free diet (which I do) I have no poblems at all with my stomach, no other food aggravates it nor does stress have any impact on my stomach. So not sure that IBS really fits. I feel that with another close relative with Coeliac that it is likely that this is what I have. I guess if I wanted to put myself through another biopsy test in the future it may give a positive result.
I do feel really lucky though as I have a couple of great GP's which I can go and see who are incredibly understanding and helpful.