You didnt mention your age.If you are young,most probable cause would be Gastro esophageal reflux disease/Stomach ulcer
.It more or less simulates Heart attack
If you are elderly man,you should exclude Heart attack(Myocardial infarction/Angina).
Consult your local doctor and get Upper GI endoscopy
abdomen and ECG done.Take complete course of treatment.
Hope every thing will be cleared.