Preg?

Okay so me and my bf had sex back at the end of august, he wore a condom, and he didn't finish, but my period was late, then in Oct I didn't have my period now it's Nov I haven't started and I have no symptoms I took a pregnancy test back when my period was late and it said it was negative. So Nov here we go with no period could I be pregnant? I mean we wore protection and didn't finish