Really fun, and different from the other game's I've played from this jam. The music worked well too, at least by sounding interesting yet not distracting from the gameplay. A young princess got attacked by a kraken in a magical inn, she ran away and tried to forget about it by playing the guitar. The story might have been from the tenth century, before guitars existed, but stories change over time, so who cares what really happened? (Or maybe the game is set at a time where guitars did exist, or maybe the music isn't trying to set the game in a specific time.)
If you're using a game engine and it doesn't automatically add its logo before the game starts, I think it would be nice to mention the engine in the game's credits. But yeah, I'm guessing that's something you could do after the jam, maybe adding a comment on the game's page in the meantime if you want to.
And nice way of using the theme! Timed platformers and moving collectibles are fun. But it's more fun to run into completely different types of games.