un explained heart rhythm

for about the past six months i have been getting strange abnormalities in my heart beat, at times it feel like it stops for a few seconds it makes me dizzy and close to passing out, then it kicks in and is beating realy hard, i have noticed they tend to happen more when im trying to get to sleep at night, the slightest little creek of a floorboard can tigger it or some tims it just comes unanounced, my doctor ran a short trace on my heart and said the rhythm was fine but it still doesnt set mind at peace everytime it happens i think im gonna die, i was wondering if any1 has any suggestion, it could be a mental issue or down to the medication im currently on for epilepsy and irratble bowl sindrome (syndrome) - carbomazipine 1600mg per day(for epilepsy), kolanticon gel and colafac (for IBS).  any advice on the issue would be much apprciated

[RNRita]

My advice?  Get a holter monitor.  These could be PVCs that FEEL like short pauses, or they could be pauses.  Two totally different ball games.  For your own peace of mind, you need to catch one on a monitor to make sure of what is going on.