we both want a baby, but bf still pulls out.

So me and my bf have been together for a year and a half. We have know each other for awhile and ended up together. He's 26 and I am 25 I have a 3 year old that will be 4 next month and he does everything for my child. And treats her as his own he's say she's his daughter and she love him to death lately we have been talking about having a baby and we both want one because he don't have any of his own and I want another one but when we have sex he's pulls out so I wounder does he really want a baby he's talks about  having a a son and he's wants one when we thought I i was pregnant last month he was so happy then when I found out I was he's was very upset because he wanted me to be pregnant what should I do???