Your symptoms are most consisent with acid reflux disease resulting in irritation and inflammation of food pipe (esophagous). Given the prolonged and chronic nature of dull pain heart problem is unlikely. However your doctor may still decide to do an EKG in the office for the record.
Reflux disease or heartburn can present as variety of symptoms like sharp to dull and vague pains, cough, vomiting, stomach upset, shortness of breath, sleep difficuilties etc. However there was an older patient with several other risk factors with your symptoms, a more agressive approach to identify and rule out a heart disease would have been appropriate.
In your case a trial of antacids like zantec, ranitidine should be tried.
I hope this helps.
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