You could have a strained muscle around the heart that makes it feel like it's your heart. Try a heating pad and see if that helps. I had the same problem for years when I was in my 20's.
My heart has literally been aching all day (Not because of emotion, just literal pain). What might it be?
I walked around with the gas pain almost 26 hours. Guess what - it wasn't gas, it was a heart attack. See your doctor if a couple of tums doesn't fix the problem. .
Some people don't find out they have congenital heart disease until well into their 50s, or even 60s. I have that, and I get heart pains due to it sometimes. That's pretty unlikely, but it's possible. More likely, it's just heartburn, but it could turn out to be pretty serious. You should see a doctor if it continues, or gets worse.