Doctor's Duty?

I am a 45-year-old doctor who practices in a specialized clinic. I've always been drawn to the dynamics between parent and child but never acted on it until recently. My girlfriend, an intelligent woman in her late twenties with a PhD, has a bit of a childish streak. She likes to be coddled, given affectionate nicknames like 'sweetheart,' and treated as if she's my little girl rather than a mature adult. I enjoy playing the role of her protector and caretaker; it’s not just in our sexual activities but also how we relate on an everyday basis. We've been together for two years now, and things have evolved since the start. When I first began to take on more of this 'Daddy' role, it felt a bit out there initially, but she liked it so much that it became our norm. I make her breakfast in bed and tuck her into bed at night with a kiss. It's not just the physical affection but also things like choosing outfits for her when we go out or reminding her to take care of herself. Recently, however, some boundaries have been crossed. I felt it was appropriate to gently chastise her if she made a mistake at work, saying something like, 'Now now, little one, you know better than that.' It's all done in fun and with humor but can come across as quite authoritative and controlling from the outside looking in. I've always been careful to frame this dynamic as consensual and mutual within our relationship. She loves feeling taken care of and is completely aware she's playing a role. I am, however, starting to wonder if there’s an issue here that needs addressing, perhaps it's too one-sided? Should I be less paternalistic in my approach? What do you think? Is this just playful fun or should we rethink our dynamic?