Why don’t I feel a connection

I’ve been extremely depressed durring this pregnancy I’m 24 weeks and I feel no sort of joy or excitement about having this child. I’m afraid that I’ll want nothing to do with him when I have him when I went to the doctor the other day I explained how I was feeling and I was told well you still have time to terminate or have you thought about adoption but I could never do that and be ok with myself afterwards. I don’t know what to do but I know that how I’m feeling now is not just affecting me but it’s affecting my other children. Has anyone ever felt like this why am I not happy why do I feel no connection with my child????