In My 40s and Still Exploring

I'm a college professor in my forties and have been with my partner for over five years now. We share many interests, but when it comes to sexual experimentation, we've hit a bit of a wall. Last night, I took things into my own hands after he fell asleep. I indulged in some CNC roleplay fantasies alone, which I’ve always found thrilling and liberating. I know the concept can be uncomfortable for some, but I felt incredibly alive and connected with myself during those moments. My partner isn't interested in that aspect of our sexual life together, which is okay, until it’s not, because now I'm craving more of these experiences. I often find myself thinking back to the early days when we first discovered each other's bodies and were both much bolder and adventurous. It feels like there are new chapters waiting for us, but I’m worried about pushing him too far if he isn’t ready yet. Am I being unreasonable? Should I seek out CNC scenarios with someone else who shares my passion? What do you all think is healthy or acceptable in this situation?