I had always pictured myself with two girls.
I think it was because I was one of 2 girls, most of my side of the family are girls.
I had DD, and got pregnant again and I was terrified of having a boy - I know girls, I have been a girl. Boys were this unknown thing to me, and I had this image of my two little girls sat playing etc.
I didn't find out the baby's sex, and when DS was born, yes, I was a bit numb.
I loved my new baby, but he wasn't the little girl I had pictured. It took a couple of months for me to get over losing that image, the two girls I had pictured growing up together. I wasn't not bonded with him, it just wasn't what I had expected.
Then, one night, I remember looking into his crib, seeing him asleep, and suddenly loving my son rather than my "baby".
It did take time to get my head round it, but I wouldn't swap him for the world.
If there is a next time, I can honestly say I have no preference. DD has been hard because she has various quirks, DS climbs things I love them both with all my heart, in entirely different ways.
You will bond with him.
Don't panic if you don't get some sudden rush of love the instant he comes out - it will come.