Friend problems out at recess ?

my friend just got dumped. i stuck up for him when people were being mean to him. i said a few things i shouldnt have about my other friend- the one making fun of him- and he told him. now, the bully hates me and for some reason so does the person i stuck up for. he keeps coming up to me and saying a bunch of stupid things. today i pinned him against a wall and told him to leave me alone. now he acts sarcastically frightened when by me. i feel if he keeps doing it i will probably beat him up. i want everything to be the way it was before his girlfriend. what should i do?