Take this for what it is, free advice.

You have full, legal, and the only custody of the baby. The father has no legal rights in this situation until he has them established. This is done through paternity testing, or by affadavit.

I would encourage you to get in touch with a local women's group to work issues out. For starters, I would tell you the following: do not have him sign the birth certificate, do not give the baby his last name, and do not get all embroiled with who gets whom over holidays. It is too early. A lot can happen in 4-5 months, not to mention a newborn is usually better served in the mother's custody for the first several months.

If you know now this is not a relationship you wish to be involved in, I would stop all communication with him. He has no 'rights' to speak of until after the baby is born, and has to have them established.