Yes, this is normal behavior for a man. You say you thought of pregnancy as it is in the movies, have you ever seen "She's having a baby" with Kevin Bacon? He goes through the entire pregnancy that they tried for, thinking this isn't what he really wants. In the end, it is.
Pregnancy is not as real for men since they do not carry a child around inside them. It is more real when the baby is born. He may even feel left out, you are sharing a special, and very important time with the baby and he doesn't get that same experience.
Unplanned pregnancies are difficult emotionally on everyone. He may need some time to adjust.