is this normal

Okay I'm a FTM, 16 weeks pregnant. My situation isn't ideal but I didn't want to abort. The dad is sooooo excited and won't stop talking about the baby, and buying things , but I can't get into that spirit. I'll buy stuff but I'm just not feeling it. I feel so detached from this pregnancy sometimes I wonder if I will even love my baby when she gets here. I'm not excited about the long nights, the crying, feeling like my life is over now that I'm having a baby. Since the dad is so excited it makes me feel bad because I can't get into that spirit. Is this normal I feel like I'm psychotic or something because I'm not overly excited