I have had chest flutters now and again and recently developed a pain in the back of my shoulder / the muscle above my left nipple to the left a bit. The last chest flutter lasted like 3 seconds and i ve had an ecg and chest xray and the doctor was basically saying nothing is wrong with me, although i ve lost my apetite and had about a week or two of sporadically finding it hard to swallow, shortness of breath.. 150/65 blood pressure etc. Should I go to the doctor again or any idea what this could be?