Late ~~

I had late for lecture this morning..... I walk into the lecture hall through the up door..... but I found everyone is starring at me.... I don't know what happen.... I quickly go to my classmates there and sit down.... they also starring at me.... I ask one of them what happen..... they said "you're late.... how come ?? you never later before.... be punctual is your principle..... how come you late ???" I want to fall down from my chair..... aiyor.... sometimes accident can occur right.... what's the big deal ?? really don't understand....