My situation was perhaps a bit different, because I'd had some losses. But when I was pregnant with my son I didn't connect to him at all the way I did with my first. At first I sort of ignored that he existed at all, then towards the end when I tried to get 'into' it I, well, to be completely honest, I resented him.

I didn't want to meet him. I felt like he
shouldn't be able to survive, he shouldn't be able to live in my womb because it really belonged to my first child. Leading up to birth I felt like I wouldn't mind the physical and emotional
challenges of parenting him, but I dreaded the cuddles, and especially our first meeting.
Maybe this is a little more extreme than what you're feeling, but in the end it was tearing me up and I sought help from a psychologist. I worked
really hard and I
did enjoy the last few weeks of my pregnancy and meeting my little one.
One thing I learnt in my last pregnancy is that it doesn't matter how you're 'supposed' to feel, I decided just to feel what I was feeling and not care. Also, I think our first babies will always have that special 'first child' place in our hearts. It's okay not to feel it second time around.