Well done in creating your very first game the old school way. It is nice to see developers produce something on actual C64 hardware instead of cross-dev and AI tools. This was how I started to develop C64 games in machine code back in 1999, but my first ever C64 game was a lot worse than what you did. But I did it using the A sprite editor, a charset from a charset collection, DMC V4.0B and an Action Replay MKVI with a built in machine code monitor. :)
As for your game, it is great fun.