for the last couple years I've had an irregular heartbeat...I actually would feel it occasionally over the last 10 years, but for 2 years now I feel it often. More so with caffeine, but I feel it even without caffeine. sometimes it is almost continuous. Its like there's an extended pause before it beats again. It used to feel like a double beat but now it feels like its skipping a beat. Are they PVC's or PAC's...and is it normal, or should I be concerned?