My heart sometimes beats rapidly while resting, my normal rate is 80 bpm, however it gets up to 106-113 while resting. I'm 28, female, 127lbs & didn't experience this until I began to have panic attacks - is it related? I've had an ecg done it came back normal, however I cannot resume exercise because my heart feels like it will beat out of my throat when exerting my self. Any suggestions?