This was a game made with a lot of passion, and I'm really impressed you got all this done by yourself. Robust mechanics, great aesthetics, and an innovative idea!
I agree with some of the other critiques I'm seeing about jumping, but would further posit this question to you: Would a triple jump make the game less fun? I personally think it'd help with navigating the space without meaningfully breaking things. Though I also didn't realize you could even double-jump until I just tried it on a whim, so I think a specific tooltip for that, maybe floating in the air near the tree when you start, would go a long way (even if it is in the tutorial text). It can be easy to miss that kind of thing.
But hey, overall this is seriously awesome work, well done!!