I've been to cardio dr, all looked good. but tonight i'm having burning pain/fade and back on upper right side of chest. i did walk 2miles after lunch?

Worth looking into: Cardiac pain is less often right-sided. However, over the internet its tough to know for sure. Without knowing details of your recent cardiology exam its hard to know how concerned to be. There are instances where a good cardiac check up did not reveal heart disease and yet it still be present. If this isn't rapidly clearing I'd get back in to see a physician pronto and have it re-analyzed.