I think it would be wise to get checked out.
I had the pain in upper,left side of back, neck, and arm April last year, but it wasn't from emotions/stress. I went to the ER and my ekg was abnormal. They said they would ignore the abnormality in someone else, but along with the pain and having my normal ekg on file they admitted me. It was the typical 3 day stay, telemetry monitoring, blood tests (cardiac enzymes? my brain is failing me right now

), ekg's, echo, walk on the treadmill. They ruled out heart problems.
Just this past week, though, I had the pain in my neck at the time of being stressed on 2 occasions. It does make me worry, but I figure I had it ck'd out and I am already under a cardio's care and have an implanted monitor, so...
(My history: I am diag with mild MVP with mild MR and mild TR, IST (inappropriate sinus tachycardia), NCS (neurocardiogenic syncope), and mildly elevated pulmonary pressure. I currently have a Reveal ILR to try and figure out why I am getting dizzy spells with everything going black. I am on atenolol and verapamil. So, I don't think I should be too alarmed, should I?)