Worried About a Secret Desire

Hi there, I'm Alex, and I work at a local bookstore. My relationship with my partner Sarah has been great, but lately, I've felt this weird pull towards something more intense than we usually do. It's like these fantasies about rough play have started to creep in when we're together. She’s always gentle and caring, which is amazing, but sometimes it feels like there's a side of me craving something else entirely. Is it normal for someone to suddenly feel this way? Should I talk to her about my desires even if they seem out of character? Any advice would be really appreciated.