Are my bad sleeping habits potentially harmful?

During the weekday I don’t get as much sleep as some people think I should. I usually get to sleep at 10— 10:30 pm and I usually wake up at 4 am. People are telling me this is really bad. I don’t really find it all that bad because after a good ten minutes of being awake I feel perfectly fine. I sometimes fall asleep during the day but thats usually when i am really bored and doing nothing of importance. Lately so many people have told me this is a bad thing that I have started to question waking up so early. I really love being up early when it is dark and quiet and no one is around. Please, do you think that this is harmful for me? Advice is severly needed. Thanks for the advice in advance!