I'd get my ducks in a row to go it alone. Work on a place to live that you can afford, or plan to stay with a family member, and on getting a job (or keeping yours and trying for a promotion), and on buying health insurance for you and the baby, and on setting up a budget for food and clothes. Save some money for a lawyer too, your boyfriend is acting like if he has an issue with becoming a dad, he doesn't have to be one, and guess what, he's going to be one whether he is wanting to still be a teenager or not. So you'll need legal advice about filing for child support. Having all of this (especially the budget) in place is useful even if the two of you do work it out, and it is going to be lifesaving if you do not. Point is, he doesn't get to run out on his financial responsibilities by taking his clothes and telling his pals he is not ready. So he might think twice about running out.
Some guys don't step up to the plate til they see there baby. And sadly some guys aren't cut out to be a dad they can't get their **** together and sacrifice the time and money for a family my husband was the same at first kept spending money on his f ing four wheelers instead of saving. It took me unleashing a hormonal beast on him to realize he's gonna be a dad. But before that we'd fight argue I left for a while at one point cuz I told him its either me and our baby or the four wheelers. It sounds childish I know but he would spend 100s of dollars a month on them knowing we needed to save for a house and car. You can try talking to him show him your not being mean or controlling that you just want what's best for your family which is saving for baby. If he doesn't understand then he's selfish and isn't ready to be a dad like he said.
I really wish I could tell you what to do, but I can't. If it was me I would talk to him about being a father, and I'd tell him that it is scary but so rewarding and if that's why he wants to leave then leave, because it's not going to change.