For The Past Few Weeks I Have Been Having Mild

For the past few weeks I have been having mild muscle spasms and a sort of constant dull soreness/tightness above the left side of my chest near my armpit. And sometimes I can feel my heartbeat beat through my chest and further left than usual while laying back or on my left side. Before all this happened I had a case of nueritis due to stress and was given a vitamin shot.