My boyfriend came inside me today but he said that there's a chance he's unfertal it's been two weeks since my period, is there a chance of pregnancy?

Yes: It is possible to become pregnant under the circumstances you described

Yes: Of course there is a chance. You don't know for sure that he is sterile and you had unprotected intercourse. It's too soon to do a pregnancy test, but if you miss your next period... Do one. And get yourself reliable birth control if you don't want to be pregnant. (And for future reference, when a guy tells you he might be sterile, don't believe it. It's Not THAT common in healthy young men)