I have bad cramps after meals, the pain is underneath the rib cage goin to the back. It become worse when I breath in or try to walk?
Could be gallbladder
If the pain is more on the right side of your stomach/lower chest, there is a decent chance it's caused by gallstones in your gallbladder. You should see your primary care provider to get an ultrasound.
If the ultrasound shows gallstones, you should be referred to a surgeon for a laparoscopic cholecystectomy (removal of the gallbladder).