Hi there -- First, you are not a hypchondriac. Okay, then, what you're describing is probably the most common worrisome complaint (even ahead of headaches) in the healthy population, and there's a reason for that: it's a scary sensation. We all have these premature beats, usually premature ventricular contractions (PVCs), sometimes atrial ones (PACs) and even in some people, some other random ones that all pretty much cause the same sensation. They are not, in themselves, dangerous nor are they diagnostic nor predictive of anything. They may occur more in certain types of disease, but this is meaningless because they are caused by so many non-disease things as well, such as (especially in your case) stress, lack of sleep, and anxiety. They also produce anxiety (for obvious reasons) so may cause themselves to increase in frequency because of concern over the rare one that is felt. Occasional ones are not even as annoying as it can get, as there are some people who have these every other beat, all the time. Oddly, they adapt to it more readily than those who have only the occasional one.
Stress,anxiety, sleep deprivation, falling asleep, digestion, caffeine (a biggie), smoking, any stimulant (legal or otherwise), exercise in some people, being still in others, holding one's breath, straining (at stool or lifting something heavy), and just plain slowing of the heart rate as after exercise, are only a few of the innocent causes of premature beats. Some people have a mild anomaly of the mitral valve called mitral valve prolapse (MVP) and these people do tend to have these and other benign arrhythmias even more frequently than the rest, but it still has no significance. The only reason to treat these is if they won't go away on their own and make the patient so anxious as to be unable to function. Then they are treated very conservatively (with beta blocker drugs or anti-anxiety meds). Best left alone, if at all possible, and if they seem extremely frequent or if there are runs of rapid heartbeat that is disruptive of activities, a simple heart checkup can't hurt and often serves to reassure the patient. Nothing wrong with that, and it doesn't make anyone a hypchondriac.
Most people first become aware of these palpitations in the teen years, as there is so much change going on, so many emotions, so many hormones being felt, so much academic and social stress. They are almost always present in all segments of the population, whether healthy or not.
I would venture to guess there is no reason to be even remotely concerned, but if you are really bothered by these and unable to adapt with reassurance, seeing a sympathetic physician (and that's the key here) can often really help, just having someone acknowlege and explain this phenomenon. It's what I've tried to do here. I hope it helps. Please follow up with us here as needed, and maybe try some stress-management techniques such as meditation, deliberate relaxation, or even a re-evaluation of your priorities in order to enjoy life more as the stressors pile up. Good luck to you!
John Kenyon, EMT, CCT
Non-invasive cardiology tech, Emergency and Critical Care technician, Critical Incident Stress Mgmt. specialist