Is this normal?

Ever since I could remember I’ve always wanted kids. I love playing babies as a kid and have worked in a daycare since I was 16 (now 24). I’ve always told myself I want kids and I couldn’t see myself not having any children. I LOVE kids and still love working in a daycare. I’ve been with my boyfriend for 5 years now and he doesn’t want kids. The more I think about how expensive they are and all of that I don’t want them. Is it normal to change your mind like that?