I don't have one, but I think this topic might help: https://www.tamatalk.com/IB/index.php?showtopic=169626. It's a similar topic that was posted in the "What Happened to My Tamagotchi?" section. Also, feel free to browse around the site when you get the chance. Chances are, you'll find the answers to many of your questions right away, rather than waiting for others to answer. Good luck! :furawatchi:
I have a Music Star. I'm also not sure what a star means. But every time it fills all my happy hearts even though it wasn't fulled before. Think it's just a thing to cheer your Tamagotchi.