When I Spilled the Beans on My Sibling's Secret Hobby...

So here’s this funny thing that happened a while back. My little sister, Lily, is super secretive about her hobbies and stuff. She likes to keep everyone guessing and out of her business, you know? But one day, she left her door cracked just enough for me to hear the distinct sound of an electric guitar coming from inside. Now, I’m not exactly a stranger to music myself...I’ve dabbled in piano, but Lily’s passion for rock music is on another level. Anyway, so I heard this amazing riff and was like, 'Whoa, sis really has some serious chops!' But then it hit me, Lily had always made it seem like she just doodled around the house with crayons and paints...definitely didn’t hint at her electric guitar skills or any interest in rock music. So naturally, curiosity got the better of me. The next day, I casually dropped a casual 'Hey, nice to see you’re into playing guitar!' when Lily came out of her room. And she froze. She had this look on her face like someone just asked for her blood type. It was priceless...I mean, not in an evil way or anything! We’ve always been close and I knew it was a misunderstanding... But after that, we didn’t really talk about it much and things were awkward for a bit. She wouldn't bring up her guitar playing around me again and just kinda stopped practicing in front of the door...which is sad because her music is awesome. So here’s my question, am I being too nosy or was it okay to just let her know that I had an interest? Should I have never brought it up at all? What would you guys do?