Pregnant

So I have a boyfriend that I've been staying with.. just for 2 weeks then I'm going back home. Anyways he's always talking about getting me pregant joking around but sometimes when we're having sex he asks "can I nut in you" I tell him no of course since I'm not on birth control. He has told me he would want to have kids with me. So we had sex and he told me he probably pre came in me idk how you'd say it but anyways pre cum. And he kept asking me if I wanted to get a plan B like throughout the day was just asking. "Do you want to get a plan B?" Over and over. And honestly I cried a lot, not in front of him but you know... he asked "so what would you do if you got pregnant?" I said "Keep it duh? If I'm pregnant, I'm pregnant" and he tells me he can go buy me a Plan B and just keeps asking about it like I said.. I wouldn't mind having his baby I really wouldn't. Oh keep in mind he has 2 little girls already but I wouldn't mind having a baby with him it doesn't bother me. So.. I started my period today.. and I don't know why I mean I do but I don't understand why I'm so upset like I'm over here crying over starting my period. With any other guy I'm so fucking HAPPY I started but with him everything's different. I don't know just some advice? Or some internet hugs lol and please don't say anything about the other 2 little girls I already said I was ok with them I really am.