Was I Out of Line?

So here’s the deal, my boyfriend and I have been into some fun adult age-play stuff for a while. We started about six months ago, shortly after we moved in together, just kind of casually at first. It was really nice; he took on this role where he called me Mommy, let me take care of him, and we did things like watch movies cuddled up together or go out to dinner with me taking the lead as his guardian. Everything felt consensual, sweet, and a bit playful, totally our thing. But recently, I decided to add in something new. We were at home one night, just him being silly and acting young. So I came up with this idea to act like we’re going on a special trip together, but I pretended that he’s still living with me as my little boy. I packed a bag for us, like it was an overnight stay in our own house, which is kind of ridiculous now that I think about it, but the way I framed it made him excited and giggly like a kid. Thing is, after a few more times doing this, he suggested something new: what if we role-play having some fun together while keeping up the Mommy/little boy dynamic? He seemed really into the idea and assured me everything was okay. We ended up going for it, and it felt intense but also very loving and consensual. Now, here’s where I need your thoughts, what feels a bit off is when we were done, he suggested continuing this play into something more serious. He wanted to start treating the role as real in our day-to-day life, like always referring to me as Mommy even outside of those special moments. That feels weird to me and crossed some lines I didn’t realize I had until now. So my question is: am I being unreasonable? Does this seem out of line for him to suggest or push forward after something that felt pretty clear was just a role-play? Or should I take it as a sign we need to talk about what our boundaries are more thoroughly? Would love your thoughts on this one.