I had a heart attack 4 1/2 years ago and it was followed by many stress/anxiety attacks.
If you're really concerned, I'd suggest going to the emergency room. That way you'll know for sure if it's your heart or not. You can then decide what to do about it.
By the way.... I no longer take heart meds due to the information I've received here on curezone.......I have no heart problems whatsoever. :)