A.B.
Go an see your doctor for reassurance as soon as you can. Tell him/her about
your family history, and your concerns. Ask for an honest assessment on your own cardio health based on your lifestyle and any risk factors. Genetics do play a part of course...but not as much as lifestyle choices. So if you do not have risk factors such as obesity, smoking, alcohol/drug abuse...you should hear from your doctor that you can rest assured of your heart health.:)
In the meantime, since you are having a hard time with physical symptoms...check out this link.
Health Anxiety- The Super Scanner
http://www.get.gg/docs/SuperScanner.pdf
Keep posting...we are cheering you on in your journey to feeling better!
S.C.