I can relate to your fear of exercise. I feel the same way at times. Sometimes just the thought of having to get up and do household chores will send me into a panic attack because I am afraid my heart rate will increase. But, just as you said, if I do it without actually thinking about it I can get through it just fine. I have always been a very active person. The bad part for me is that I am a neat freak. I will panic if my house is a mess, and panic at the thought of cleaning it. However, I have been through this same thing a few times before. It will pass after a while. I just try not to give in to the fear and go on with the things that have to be done. I wish you the best of luck.