What Causes Constant Chest And Upper Back Pain?

hello, I had a recent physical with required through my work and the doctor brought to attention me having a heart murmur, which is something I have never been told before. I have now had constant chest pain and upper back pain that is very achey. Not sure if this is anxiety built up or a concern to be addressed. I am a 22 year old female, 115 pounds, quite active and healthy in lifestyle. I am a triathlete, I also had an instance the other day during a swim workout where my lower have of my body went numb towarrds the end of an intense workout where I had to quit to get the feeling back.