Ain't nothing wrong with that. One of my friends got a vasectomy when he turned 18/19. A lot of people don't want kids and that's fine
I probably should have said why it's weird. First he has a daughter that was born a few months ago. Secondly I've followed him for nearly 2 years and that whole time even upto a month ago he has talked a lot about wanting a big family and wanting at least 6 kids, and even said several times that his ex ( the baby mama) wanted him to get snipped, and that he never would do that no matter who asked, not even if they had a gun to his head. That is why it's weird
he went from saying all that to getting snipped in matter of a month.
P.S. he's not back together with the baby mama as far as I know he's single.