My son is not ready to not be the baby and I feel so bad.

My baby is only two and a half, I’m already almost in my second trimester and he’s still breastfeeding and doesn’t go to school yet. He talks and I’ve asked him does he want a brother or sister and he said no every time 💀😭. He’s also still very spoiled,doesn’t like to share,is on my hip or my boob all day and needs so much time and attention 24/7 like all babies do. I feel like he’s not ready to not be an only child and to not be the baby of our family anymore. I have extreme mom guilt about this. I wanted to give him at least 5 years before he had to share his mama. And for him to be able to understand what’s going on. And to make things worse she’s (I feel like it’s a girl) due one day after his birthday. The guilt of this has weighed on me so heavy it keeps me up at night. And his dad agrees that he thinks it isn’t fair to him and even suggested that I abort, which I am not okay with. But don’t know what to do or think about this.