You not feeling your heart beat is a serious problem, but if you're alive and well then it could mean that your blood pressure as lowered. I have that sometimes and sometimes it happens when I go to sleep, or sometimes it doesn't. Usually feeling your heart beat is caused by high blood pressure (since your heart has to pump harder) or it could be you sitting in a position that squishes an artery, thus, making you feel your heartbeat. If you don't feel your heartbeat, then it is nothing to worry about. It indicates that you have low blood pressure. If you have swelling in your legs it could be a sign of DVT, usually a DVT is in the vein, and not in the artery, which coulda cause you to not feel your heartbeat. If you have swelling in your leg after a change in your lifestyle, then you could have heart failure. If you have what I said, then you should go check it out as soon as possible. Heart Failure is reversible if caught early.