My puppy is limping! is there a vet out there? helpp?

my 7 month old jug (pug and jack russel) was outside playing yesterday. she was running very hard, more than normal because she was "playing" football and basketball. my boyfriend was playing rough with her too, because she likes a challenge. he was slidding her and chasing her and stuff. then my brother accidentally stepped on her paw and after that we noticed some limping. im guessing that she has a sore paw, or pulled something while playing. does anyone know what i should do or what could be wrong? thanks :]