I accidently sold someone a phone on craigslist that had a bad esn. hes saying hes calling the police?

i bought the phone from someone for really cheap. i should have known. he is saying he will call the police. he has my phone number. i would give him his money back but its already spent and im 17 with no job. can i get in trouble with the law or are all craigslist adds "as is". thanks