I am experiencing a pounding heart in the night from time to time. No pain with it. Other times I have had pain in the chest wall only which Dr s have said is not in the heart. I sometimes Feel emotionally unstable for no apparent reason, and I have a lack of energy. I am 75 but in good health and only on asprin, no other medications. I take vitamin supplements, eat healthily and am still working as a Christian pastor. Every other time I have had my heart checked out with cardiograph s, stress tests etc it all comes up that everything is ok. Apart from a slight enlargement at the back of my heart tests have come back fine. Last night the pounding lasted about 2 hours. I suffer from daily leg cramps, particularly at night which means I get up several times a night to walk them out. Magnesium and other minerals does not seem to make any difference. Thank you.