All in good fun :)
I usually say good morning until noon, and refer to 3 in the morning when people call me that late/early.
See, now you are half-contradicting yourself! You say you refer to it as morning, then you go on to say that it is both early and late. So is "January 3, 2003 at 3 AM" January 2nd's late night or January 3rd's early morning? Technically, it is January 3rd's early morning, but human perception and thinking comes into play. Even the simplest things can become confusing, because all it takes is one person who thinks differently than the majority of others.