I work with a lot of young adults (teens to early 20s) and all the girls went baby crazy, rubbing my belly, etc when they found on I was pregnant.
All the boys got really weird... one decided to try and discuss ovulation and the length of pregnancy with me (he told me it wasn't weird to discuss this because his brother's wife just had a baby....) and another one started telling me to name the baby after him. One is training to be an EMT and told me he would be able to take care of me if I went into labor... O.O
Guys are weird. I can never predict how they'll react to things.