I sometimes have sharp pain on left side between heart and lungs. i was born with a heat murmur. what are the symptoms for heart murmurs?

Depends...: Murmurs are a sound made by turbulent flow across the valves, or a hole in the dividing septum between the ventricles, or rarely a small tube that stays open which should have closed at birth, the ductus arteriosus. Symptoms could include shortness of breath or swelling in your feet if they are bad, but should not cause chest pain. Get an echocardiogram and see a cardiologist.

Sharp chest pain: Sharp pains usually indicate something other than cardiac pain. If you were born with a murmur, do you have a diagnosis? Just knowing you were born with a murmur does not allow me to advise you further.

Echocardiogram: Get one & have a consultation with a cardiologist to get evaluated & get answers.

The "twinge": Most sudden sharp pains here are "texidor's twinge" which i believe results from a fold in the membrane that lines the chest wall. It usually stops if fill your lungs with as much are as possible. Sharp pain here is almost never of cardiac origin. A majority of youngsters have a murmur at some point if you listen hard enough. If you feel well today, be thankful.