Does it get better? I'm having a hard time picturing us having a baby..

We are 18w1d with our first. He/she is a surprise baby. We just got married in May and I'm still in nursing school for one semester. We have has two ultrasounds (10w and 12w) and the heard the heart beat(I think I'm not sure though) at 16w. But I'm still in denial. I never had any pregnancy symptoms except for fatigue but I dont know if that's from pregnancy or nursing school. Im not showing and I havent felt it move. We hopefully will find out next week what we are having and I hope that makes it finally seem real. I cant picture having a boy or a girl.. I honestly cant picture us as parents. I'm starting to feel like a failure of a mother already because I cant make myself believe our baby exists. I dont know how to make myself believe it. And I'm so worried I'm already doing things wrong and something is going to be wrong. Does it get better?