If your talking about a hole in the heart, VSD is more common than ASD. So without any further information i will assume VSD rather than ASD

An echocardiogram will immediately tell you which is which. It is also important to know what kind of treatment she has received as it may affect the course of the condition a lot.
Okay ASD and VSD are both congenital problems. In simple terms something went wrong during the fetal development leaving a hole in the heart.
"Heart pain" is not the usual symptom though. Better go and see a doctor.
Good luck. =]