I'm 27 years old and was physically active until I had a foot operation in Oct 04 which restricted me from exercising (running 4 - 5 times a week and running races once a month ). Ever since the op, my heart has been beating very fast - worse than before. When I am sleeping and get woken up suddenly - mostly if I've been asleep for less than two hours, I wake up with the heavy and fastest heartbeat. When this happens, my chest would feel very heavy and I would be thirsty. The heatbeat would slowly go back to normal and I would be fine again. I also have the fast and heavy heartbeats when I'm anxious about something but not as bad as when disturbed from sleep. Is there anything I should worry about?