My DH wanted children, then went off the idea of having children when I was pregnant! Too late then! It wasn’t easy for me. He wasn’t going to stay with me during labour. A colleague told him he could kiss goodbye to our marriage if he didn’t. He did support me and our daughter wrapped him round her finger from the moment she was born and hes still there 40 years on. He went through a similar reluctance before our first grandchild was born. My daughter and I both laughed at him and foretold that he would be hooked. We were very right. He adores all his grandkids.
I think his feelings are not uncommon, though maybe a bit extreme before the birth of our daughter. I put that down to the fact he hadn’t had a father of grandfather. The reality of the baby made all his fears and feelings disappear.