It can happen sometimes. It's called a "sympathetic pregnancy". It's not common but it's not unusual either. With time, he'll feel better. You just have to help each other through it.

yes, they are called sympathy pains. also come with sympathy cravings and contractions xD

Some guys are more sensitive to the girl and what she's feeling and they can "feel" what she feels.

Yes, they can - and do.