This is absolutely lovely. Enormous fan of the concept, visuals, story, etc. The visuals and nonverbal storytelling reminds me a lot of Hyperlight Drifter - one of my favorite games.
Only criticism is the movement. Like others here, I found the jumping in particular to be nonresponsive and frustrating, especially for the platforming sections where precision is important. Maybe you could allow for some aerial control of the character? Or make it such that jump height can be better controlled by how long you hold the space bar for? In general, as well, I think the controls could use a bit of help to feel "fluid" like you'd expect from a blob-creature.
It might be worth looking at Rain World (another sick pixel platformer), in which you control a cute, squishy slug-like creature. I think Rain World pulls off "fluid" controls extremely well, and a similar approach might work well in a game like this.
Regardless, what you already have is EXCELLENT, and I'm hyped to see where this project goes in the future :)