Conflicted Adult Little Play with a Former Student

I've been a high school teacher for five years now and have always prided myself on maintaining professional boundaries. I never let my personal life interfere with my work or responsibilities towards my students. However, about six months ago, I started experimenting with little play as an adult and found it incredibly freeing and enjoyable. Recently, one of my former students from three years ago reached out to me online. She's now 18+. We had a few innocent conversations, catching up on life. Then, unexpectedly, she mentioned that she was also into adult little space play and asked if I ever played little. I was taken aback but honest with her, I confessed about my secret interest. We agreed to keep it between us and decided to meet for a coffee date, which ended up being an adult little play session at her place. It felt like stepping back into high school in some ways, but she's legally 18+ and completely consensual throughout. Afterward, I'm left feeling confused, I feel guilty but also strangely connected to this student again. Is it ever okay for a former teacher-student dynamic to evolve into an adult little play relationship? Am I overthinking or being overly cautious? Your thoughts would be much appreciated.