I recommend that you visit a cardiologist
to discuss this. A heart murmur is a sound made by blood flowing through the heart in a turbulent way. After your doctor
hears a heart murmur, figuring out what is causing the abnormal sound is the important question.
In many cases (especially in young people), a heart murmur is a normal variation. In other words, there are many people that have them, and they are of no consequence and represent no pathology or disease. In some cases, a heart murmur might mean an enlarged heart (hypertrophic heart). People with an enlarged heart might be a greater risk of sudden cardiac death or heart failure. Heart murmurs are sometimes due to an abnormality in a valve of the heart. Because it's sometimes hard to tell what is causing a murmur, additional tests usually need to be done.
Again, I suggest that you schedule an appointment with a cardiologist. The cardiologist is likely to listen to your heart carefully first before performing any additional tests. This physical exam alone is often enough to tell what is causing the murmur. Nevertheless, in most cases, the doctor will want you to get an echocardiogram
(an ultrasound of the heart). This is probably the "additional test" your doctor wants you to have. An echocardiogram is a non-invasive imaging test of the heart that only involves an ultrasound probe being placed on the chest.