What Causes Sharp Pain In Chest Of Person With Heart Disease?

Hi, I am 21 years old and I was diagnosed with a heart murmur 2 years ago. I would get these very short yet sharp chest pains that last a few seconds. I feel like someone is squeezing my heart and it gets even worse when I try to take a deep breath. Heart disease runs in my family and I don t know if these symptoms are serious or not...Thank you