My Wife's Unexpected Turn On

I've been married to Sarah for ten years now. We have a healthy sex life but it tends to be pretty straightforward, nothing too wild or unconventional. Lately though, I've noticed something different happening during our intimate moments. She's become oddly intrigued by a bondage element that we never explored before, specifically the idea of me wearing handcuffs while she takes control and guides us through the experience. The first time it came up, she was shy but insistent about trying it out. To be honest, I felt a bit awkward at first as she wasn't typically into anything like this, but her enthusiasm made me reconsider my initial hesitation. We gave it a go last night and, surprisingly, both of us enjoyed it immensely despite the initial discomfort for me being restrained. It's been an interesting shift in our dynamic. So here's where I need your thoughts: Is it common for long-term couples to explore new kinks later on? Or should we be concerned about the sudden interest? What advice would you give us to approach this exciting but slightly uncharted territory together?