I need some advice ladies

So I met this guy online and we texted for like 2ish weeks because he lives an hour away. Before our first date I told him I like to wait three months into a relationship to have sex. Most guys bail but he said it was fine so I was thrilled. Our first date comes along and we go to a movie and everything is fun. We got back to his house and started fooling around. At some point he was fingering me,stopped and decided to "surprise" me with sex. I was caught off guard and told him it was ok, but it's been bothering me and we've been seeing each other a couple weeks now and he constantly wants sex... I told him I don't want to have second anymore but I don't know if he's actually gonna listen...what should I do?