Broke up with my bf

I broke up with my bf about a month ago. I am currently 31 weeks preggers and he's causing so much drama. He's been threatening to take my baby away from me when she's born. He says he already has spoken to his attorney. I don't have a very good past and he's planning to use that against me. But I've been good and have done nothing nor plan to do anything. Is it wrong of me to not want to use his last name for her if we are not together? I'm so confused and don't know what to do exactly.