What Is The Treatment For Chest Pain And Dull Ache Below Xiphoid Due To GERD?

Question : I am overweight 38 yo male sleep apneic with cpap for last 7 or 8 years. Have had some degree of stomach and chest symptoms on and off for the last year. Everything from gastritis to sensations in my chest that brought me to the ER to R/O a heart attack (dismissed as altitude sickness/panic attack). I later had an EGD which found nothing but mild generalized gastritis and a “2cm Non-Sliding Hiatal Hernia”… Prior to all of this, I had another sleep study done b/c I felt over distended in the morning and thought my symptoms might be related to my cpap. My setting was indeed lowered to 10 from 13 and things seemed to be better… but the last two weeks I have been having alarming sensations as I am falling off to sleep and even twice while I was fully asleep… where I awoke with a sensation of a giant knot in the center of my upper abdomen, an brief feeling of not being able to breath and generalized feeling of doom. This sensation causes me to leap out of bed after which I can breathe again and the knot in my gut/diaphragm goes away within a few moments. There are remints sometimes of a mild dull ache just at or below my xiphoid process. This all seemed to start after a two week flu session of intense coughing…. My theory is that my HH was either worse than diagnosed or that it has become worse after all the coughing and that between laying down and the cpap expanding my diaphragm… my gut is sliding into my chest and causing these symptoms… Any different theorys? How can I test them / know? Will a CT with contrast reveal an HH if my stomach is in its normal position at the time of the scan? (I ask b/c of all the other things that might be wrong that a CT would show…as it was suggested). Should I just ask for another EGD at the Risk of seeming like a Hypochondriac?