I am a 36 yr old slightly overweight female, smoker, who has has a palpating heartbeat for going on a week now. It never gets over 100 bpm, and I have had a few tests run at a local ER (EKG, chest X Ray, etc) that shpw nothing. Just tried to sleep and it felt like my heary flipped in my chest. No pain, just an ache in lower part of left upper arm and a headaxhe I am 90% sure is sinus related. What should I do?