You should not worry about having a body that functions in a way that is a bit outside of the norm if this doesn't cause problems for you. If our distant ancestors had the intellectual capability to worry about such things, we could never have evolved to become humans. A healthy human being can after all also be considered as a pathological version of Australopithecus.
While not all that common, there are people who only need about 4 hours of sleep. Because this gives them a lot more time in the day, they tend to do well in life. At least they are overrepresented in the group of CEO's famous scientists etc.:
Some more examples here
Marissa Mayer, currently the CEO of Yahoo and previously the renowned Google executive, gets very little sleep. It should come as no surprise--considering that she infamously worked as much as 130-hour work weeks while at Google--that Mayer prioritizes work over rest. She reportedly gets only four to six hours of sleep every night, recharging by taking week-long vacations about three times every year.
Whatever you think of Martha Stewart, she's a woman who needs no introduction. Stewart has achieved an astounding amount, and she hasn't done it by sleeping. Somehow, household name Martha Stewart manages to not just get by, but also to thrive, on four hours or less each night.
None of this proves that sleeping for 4 hours in any particular case is not a sign of some underlying medical condition, nor that in general, sleeping for 4 hours per day is not linked to adverse health conditions. However, what we can say is that the mere fact that someone sleeps for less than four hours per night instead of the recommended 8 hours, isn't necessarily going to be a problem. It won't necessarily prevent that person from doing all the hard work necessary to become a real estate mogul, take care of a big family and still have energy to spare to run for president of the United States.