Wooziness, pounding heart/palpitations, cough, aches..?

for the past month or so my heart has been pounding hard enough to shake my headboard when i lie down to sleep at night. for the past two weeks it's gotten worse so that i wake up every day with fluttering heartbeat feelings, erratic heartbeat, and it pounds so hard every time i move that i get woozy enough to stumble a little. today it's at it's worst, i've had the shakes, i'm so woozy and achey, and the heart is pounding like crazy, as always. i'm wondering, can all this just be stress? if not, anyone have any idea what might be wrong? i don't have a fever that i'm aware of. i'm just starting to get increasingly curious/concerned.