Lack of connection with baby

I'm almost 28 weeks pregnant, and have struggled developing a connection with my baby. This is my first pregnancy and it took me by surprise. Don't get me wrong, I am excited about adding him to our family, and I know that once he is born I will be overcome with love. It just isn't happening now. I try to tell this to my mother and she keeps insisting that I'm lying because I don't like to be a "mushy" person. It just hurts to not have that connection and on top of it to be told that it is impossible that I don't. 😧