I am a 22 year old male in overall good health. I used to have a first-degree heart murmur (functional only), but I don t think the doctors can hear it anymore. I have been using marijuana regularly for about a year now (mostly vaporizing), and every once in a while, after using, I will feel mild pains that feel like they are coming from my heart. I imagine that it s probably muscular, but it does appear to be coming from my left side only. What kind of doctor should I see about this problem? What could it be? How could they test it?