I used to see an old chiropractic doctor who swore by this method to help hiatal hernia:
Upon arising in the morning stir one teaspoon of cayenne pepper powder of a good heat into a large glass of water and drink. Then jump flat-footed and hard on the floor several times. Or consider jumping down off a small height such as a stair.
The theory was that the stimulation of the pepper along with the weight of the water in an empty stomach while landing hard would pull the stomach downward through the diaphram opening where it is protruding and causing the symptoms. At the same time the extra circulation would tighten and heal the area. If you are not used to taking hot cayenne, you may need to gradually build up to that amount, especially on an empty stomach!
Also, if you have not done any colon cleansing and liver flushing recently, you might consider studying up on that. The reason is that the gradual build-up of toxic sludge and matter such as gallstones in the digestive tract can cause upward pressure in the abdomen. Some people have been relieved of such symptoms simply by tending to the state of their digestive organs.
Hope this helps. Best wishes.