he was playing around with his pals near your table. Then their games get a little bit out of hand, as Saejo, the class idiot, and best basketball player, falls, and bumps your table, causing the things on your table to fall off. To be worse, your water spilled on your homework

"Oops... Sorry."

he says, as he stands up, and goes back to playing around with his pals, and didn't even show much apology after what he had done.