Why do i get heartburn that's hurts so bad it makes my back and chect hurt?

Could be ulcer: Heartburn that severe probably should be evaluated by your primary care physician. While it may be just heartburn, pain radiating to the chest and back can be a sign of an ulcer, including one that could be going deep into the back part of the stomach. Other serious causes of abdominal pain that goes to the back can be serious problems such as an abdominal aneurysm. Best to be seen.