I've had stomach issues for some time now, probably going on a year. First they thought gall bladder, etc, but an upper endoscopy came back clear, and it seems to come and go. Anyhow, I would describe it as a "squeezing sensation in my upper stomach, just below where the ribcage meets". I'm wondering what most likely causes this? I really do not want to take medicine. I'm female, 44yrs old, weigh 120lbs, and workout almost every day. My medical history is high stress (daughter had leukemia and a high stress family business). Also had a gas leak and suffered low level carbon monoxide poisoning in 2012. Found it only after we were having memory difficulty, concentration, and other motor issues in the family. Trying to figure out what might be upsetting my stomach so terribly to cause this squeezing, and any suggestions.