Love that music! It sounds like if toby fox used real instruments when making undertale, and also made it significantly jazzier.
The voxel art aesthetic is also really nice.
The jump feels floaty and also not high enough. I think you should also tweak the colliders in that first area with the bottles. Ill be honest, I couldn't get past the part with the sponges in the sink.
You definitely should have checkpoints (maybe you do but I didn't get to them). Your game is difficult but not in a fun way. It feels unfair ya know? The cylinder colliders at the start are difficult to stand on while in 3d mode, and my jump is just barely high enough to get to the second cylinder. Switching modes while mid-air on the first challenge also seems a bit much.
Its also possible that I'm not your target audience, as I'm not very good at video games in general.
Unrelated, but your 3d camera clips through some objects, and it looks kinda weird. You could try having the geometry fade out as it approaches your camera's near clipping plane to make this look less jarring. However, it would be even better to avoid this problem altogether by designing your level and camera so that this never happens.