I get that sting feeling in my chest it lasts for a couple of seconds, its sometimes sharp and the pain is usually not in the same place in my chest?

I am sorry: but this can't be diagnosed with the available information.

Likely not heart but: Chest pain is nothing to ignore! The potential origin of your symptoms includes: heart, lungs, mediastinum, esophagus, musculoskeletal, pericardium (sac around the heart), pleuritis, bronchiitis, or referred pain from a remote site. Your doctor will be concerned about accompanying fever, blood with coughing, vomiting, shortness or breath, difficulty reclining, tenderness. Get checked please.

Texidor's: This is almost always the "twinge" or "stitch", probably a transient wrinkling of the pleura.