i have NEVER been so dissapointed over a game ending (because i wanted to keep playing), you've somehow managed to make a non combat focused metroidvania for a game jam and you should be proud, the game was amazing, it really reminded me of games like hollow knight or even dark souls, not in combat but in worldbuilding, without any lines of dialogue you've managed to convey so much of the world and who the player is, the game is gorgeous and i'll definetly copy this single color pixel art style for a project of my own some day because i loved it.
I want to know more about this world, i want to keep exploring, what was the green being that comes out of the ground? why is everything white including the player? why are we bringing life to the world? you're right thinking this game has potential, it's definetly one of those games that feel bigger than they are and i loved it.
There's some improvements too, first of all, the controls are a bit badly positioned, specially C for the bubbles, and while you can jump with space bar, in game you only mention enter. Also the bird catching with the bubbles was by far the worst part of the game, the birds fly away off screen, where bubbles cannot reach them, and while you can reach them yourself by spinning the world properly, it's really hard. Maybe reworking how the birds or the bubbles work would be smart.
Another area of improvement is just a little bit more player guidance, im not saying add explanations or yellow paint, that would completly ruin this game, but maybe a little jingle when the player is doing something to progress, for example when you're creating grass at the start, the music could do a small change while you are making new grass and return to normal while not, also some particles could be included and some camera effects. Also, the "You're smart enough to figure out what to do" sounds a bit condescending, maybe different wording would be better!
in terms of the music, it was fine, it fit the theme, but this game has so much soul in it that you could notice the music wasn't made by the same person that made the rest, if you keep going with this project i'm not going to tell you to learn music theory and sfx, but you should definetly pair up or hire someone that can handle that with as much passion as you've put into this game.