I feel like I’m spiraling

I just found out that I am pregnant and this was such an unexpected surprise. I for some reason assumed that plan b pills would stop a pregnancy from happening as long as I took it within the first 24 hours. I feel bad about the thoughts that I’m having. I’m just not ready for another baby yet. My son is 16 months old and he is such a handful. Because of him I already feel like I don’t give my 7 year old daughter as much time as I should & I think another baby would just be very unfair to her. I also don’t feel the instant love I felt for my other children. I feel almost disappointed. My problem is I voiced these things to my fiancé and he completely ignored it basically saying “it’ll be fine”. I don’t want to come off as ungrateful but I can’t help from thinking about how I’m just not ready for another child yet. 😔