What can cause a sharp pain in the chest from time to time? can that be normal? ive had a normal ekg, echo, blood work and chest x ray? not worsened by anything and not doing anything physical when it hits. lasts a few seconds and goes away?

From your description, I suspect these fleeting sharp pains are emanating from the rib cage & not the lungs,heart or esophagus. An irritable rib cage nerve or intercostal muscle can cause such symptoms. I think your normal test results are reassuring that you're not dealing with anything serious. If you still have concerns you could consult a pulmonologist.