Advise please

So I am 5 week pregnant with my first child. My boyfriend and I always joke around about having kids, and boom I’m pregnant. Now he is saying that he isn’t ready for baby. I’m happy to be pregnant, I had a miscarriage 4 years ago. I just want us to be on the same page. He never pulls out and I’m not on birth control. So what did he think was going to happen? I am ready to step up and be the mother I know I can be. But what should I do about my boyfriend? Help please