I can see the vision, but there's just a little too much with it that's still not fully developed. For one, it's really hard to get a sense of timing when you don't have an indicator of where Gigi's attack lands. One might initially assume it's around the same area or in front of the car, maybe. But it turns out it's a whole area in front. That said though, the hit detection's a little wide and too forgiving that you can tap out of beat by a bit and still get it. Double notes are hit at the same time because I assume their collisions overlap and there's no hit detection counter/limiter that prevents this from happening. And speaking of the beat itself, the mapping also feels off in some sections, but I do think that for the most part it seems aligned with the song. The pebbles seemed unnecessary, but I know what you were emulating so I understand why that's there.
Overall, I think you have a good idea and were able to do what you could as a solo dev in the time provided so I can't really be too hard on you. Besides, we do this jam for fun, and I did still enjoy some of the time I tried out your game; and I hope you had fun making it too, and I think that's more important. Good job and congrats on the submission! :D