I'm experiencing terrible shortness of breath even just while talking or sitting. I saw my Dr today about it and he wants to test me for some rare heart problem that occurs in pregnancy. I'm 17 weeks. I've had heart palpitations in the beginning and before I was pregnant, and I had a heart murmur at birth. I've never even considered the possibility of a heart problem and now I'm stressing out badly about it. I'm hyper aware of my heart now like I can feel it in my chest. I had an ekg today and will have an echocardiogram done soon but I'm so nervous. I'd never even heard of heart problems in pregnancy. Has anyone gone through this?