How do i explain it to my dad with out sayin it bad?

today at recess me and my friend celi were out side and this boy michael was tied up in his sweat shirt and was getting our faces!! so i pushed him and he slipped on a jump rope and fell and got a bloody nose. i didnt mean to hurt him. then one of my teachers stupid mrs.clarisy send me, celi, eli and michael to the office and i started to cry alittle. then eli did (alot for a 6th grader) and michel kinda did. celi didnt i didnt get in trouble. and i told my mom but how do i tell my dad???