Some of the most common symptoms of leaky heart valves are:
Which valve did they say it was that you have leaking?
My husband (48, and very fit) has a severe leaking aortic valve and it is a matter of time (depending on chamber measurements) before he will need to have it replaced. Every night he suffers from heart beating super fast, chest pain, ect. I told him I want to get a recliner so that when he has these symptoms, he can sleep reclined in it but not lie flat.
I am sorry you are going through this but want to encourage you that modern medicine/ technology is incredible. With your doctors' care, you should be fine, even with replacement.
Take Care and God Bless!