Whats the diffrence from a ruptured aortic or just a gas pain in the stomach?

Life and death. A ruptured aorta is a generally rapid and lethal illness demanding immediate assessment (echo and angiography) and, if feasible, urgent surgery. The pain (often in the back) is severe, prolonged and not debatable (no doubt bad things happening). Gas pains can be short in duration, come and go, and relieved by burping, passing gas, or antacids. If you're asking, it's not a ruptured aorta.