Thank you for your question. From your description, the cause of your symptoms is most likely due to acid reflux that is typical of gastro-esophageal reflux disease or GERD.
However, other non-gastric causes of similar symptoms include heart disease - especially if the pain occurs on exertion (eg climbing stairs) and radiates to your jaw or left arm.
Epigastric pain that radiates to your back and shoulder tip may also be clues that it originates from your gallbladder (eg gallstones) or pancreas (eg pancreatic inflammation or pancreatitis). Gallstone pain or biliary colic is often worse after meals, and may be accompanied with vomiting, fever and jaundice (yellowing of the eyes).
I would suggest that you seek a formal consultation if these symptoms persist to ascertain the diagnosis and receive the appropriate treatment. As some of these conditions are potentially serious - I would recommend that you see your family doctor or gastro specialist soon.
Many thanks,
Dr Kieron Lim