Hi Nina,
Yeh, it's always a good idea to get these things checked out. Like Misty, pounding heart was the first symptom I ever had. Just every now and then my heart would pound. Strangely usually happened when I was being still, like watching TV was a big one. I asked my friends about it and a few said they had it now and then. I've since had it checked and I'm fine. When I got panic disorder the pounding would happen in accordance with an attack, still does. I read someone say on here once, can't remember who, But they said that the human heart can take a lot of stress. That it's good at regulating itself and slowing down if absolutely necessary. Put my mind at ease a bit knowing that.
hehe and I really love this forum too, Take care :)