What Causes Stomach Pain Followed By Locking Of Back Muscles?

Question : Hi, I have had stomach pains, which locks most of my back muscles up, from 3am every day for the last 12 months or so. I have been to doctors and massage places, acupuncture places, had x-rays for back problems or arthritis etc, and to natropath, chiro etc... I still have these problems. I do believe it is a gas build up in the stomach, and it feels like a twisted bowel at a guess.. I actually have to twist my hips around to have a bowel movement often... I feel the stomach pain about under or behind the LHS lower rib, and it amplifies throughout, until a shower or I move around at work etc.. It can release gas both ends sometimes to relieve etc... I believe stress is one of the major issues, but not sure what to do.. I am fairly fit and healthy, I eat well enough, I don't drink or smoke, I am hydrated enough, and I do exercise and stretch a bit each week(martial arts).. What do you suggest? Thanks