On And Off For The Last Few Months After I

On and off for the last few months after I have a loose bowel movement I seem to get a pain right under my sternum. I have no trouble swallowing or food getting stuck. I have the pain for a day or two and then it goes away for a few days. I have tried acid reflux medication which doesn't seem to help. I have also tried to eliminate certain foods thinking it might be an allergy of some sort. This did not help. I also have a lot of gas some days. I had a ct scan of my lower abdomin with contrast about 6months ago and it was negative except for enlarged pelvic veins. My bowel movements lately seem to give me a diaper rash after I go as well.