http://www.medicalnewstoday.com/articles/138503.php The following link above confirms your suspicion about the possible correlation between chest pain and stress. I suffered from this as well at the age of 40, and resulted in a trip to the emergency room. A tranquilizer injection made this pain disappear.
Chest pain (angina) is difficult to diagnose for any health care provider if your cardiovascular diagnostics were determined to be within normal limits. This is of course a good thing. Yet if your discomfort is persistent, and I say this as a layperson, you may want to get checked out for an ulcer or what is called GERD (gastric esophegeal reflux disease). Both have to do with acid in your gastro-intestinal tract. And both are treatable.
There are other symptoms associated with a myocardical infarction (heart attack), such as syncope (fainting), and what may be a crushing pain in the center of your chest. These may be things you should be observant of as you progress