My ex is trying to take my almost 3 month old baby to stay with him for the weekends and he lives 2 hours ago. Am I wrong for saying no because my baby is still really small. I always tell him to come visit during the day but just no overnight stay with him. Plus he's a year younger and still in high school..

I assume there is no court orders at this time. Unless there is you are in control. And until there is court ordered custody, you should not let the child out of your sight. Assuming he is listed on the birth certificate, he has an equal right to the child. So if he takes the child, he can refuse to return the child and force you to go to court for custody/visitation.

You need to go to court first to establish primary custody and child support. He can then ask for reasonable visitation. Until the child is older that will probably not mean overnights.

You should arrange perhaps a third party where he can visit with the child or some locatoin other than your home, assuming you are no longer dating or a couple, he may not want to have to "visit" you at the same time.

All he has to do, is go to court and get a order for visitation, and he will be able to do this most likely with no problem, since it is his child also.

But as noted you need to get a child custody agreement though court,