Will I get pregnant this way?

So I’m 20, my boyfriend and I have been together 7 months. So my mom told me that I should get on birth control but I told her no because I don’t wanna gain weight and I just simply don’t do well on it. It makes me emotional and depressed. I’ve tried the patch, the pills, etc. so now I’m on nothing at all. And my bf has really bad timing with pulling out. He never does it in time. But the point here is that my mom says that if I don’t stop, that I will get pregnant this way. But I told her that even before birth control, I never got pregnant so to me it’s like I can’t have kids or if I can it’s very hard for me to. She said she doesn’t wanna raise any more kids and that I’m not responsible enough to be taking chances with having a kid. Is my mom in the right that I could get pregnant?