I feel it lightly, when I apply pressure to my left side chest muscle I feel it, I run everyday and my heart beats are fine, I do not run out of breath, I never feel dizzy. The pain goes away when I take pain killers.?

Emergency. Potential causes of this chest pain include viral illness, pericarditis, pulmonary embolism, viral illness and some less common problems. An urgent visit to ones doctor, a cardiologist or to the Emergency Dept is warranted to enable a careful search for the cause of pain.