It's quite an undertaking to attempt to make a Metroidvania game not just in a game jam but with such harsh restrictions. I'll be honest, I dropped the game soon after the tutorial (first chapter?). The mechanics were actually sort of interesting, and I enjoyed the puzzles in the linear section, but as soon as the world opened up my enjoyment dropped. I think there were two reasons for this.
1) I felt that the game's puzzle mechanics don't mix well with Metroidvania mechanics. It's less fun to explore the world when making a wrong move can make me fly in the wrong direction and making me have to spend time getting back. I suspect people will find this point very subjective but it did hurt my enjoyment of the game. I think I would have kept with the game longer if traversing the world would have been more conventional and the puzzle mechanics are contained to separate areas.
2) I feel that the graphics were too monotonous for a Metroidvania. It's really hard to navigate the world when it's hard to distinguish between areas. Now of course this also comes from the limitations of the jam. I don't think it's possible to create enough visual variety at such a low resolution to make an enjoyable Metroidvania. I did notice that you tried hard though; different backgrounds, different walls, etc. Unfortunately for my aged eyes it was just noise.
All in all, I couldn't see where to go, and it was hard to explore. (Or maybe I was impatient.)
The controls were a bit irritating at first but I was able to get used to them. It's really tough to come up with intuitive controls for a game like this because some people will find absolute directions more natural and others will prefer relative ones. If you want to go the extra mile you might consider adding the option to choose between the two.
The pixel font was hard to read. I think you could have afforded to for a higher resolution because usually there was some empty space next to the tutorial messages that you could have used.
Even though I didn't complete the game it's quite obvious that a lot of love went into it, possibly even too much! I think I would have enjoyed the game more if it was just a linear puzzle game with simpler graphics.
Thank you for reading, I hope you'll find my feedback useful and constructive!