help what do i do - and the music has some bugs

I think it's a fun little concept,
I think if I were to improve upon a few things they would be these:
1. Collisions, the current ones are extremely...imprecise and that makes it a bit frustrating to judge stuff
2. I think the actual growing of the square could be centered, this way, there's a better perspective on how you're growing, rather than growing towards one side
3. I think the art could honestly be more simple, just black/white, with simple outlines for things, and that would really make the game pop more visually

Otherwise, a great proof of concept for a beginner game, keep it up!

Cool concept, plenty of potential here

Interesting concept. I was thinking there would be more than just 2 states, thin and thick.

Moving forward with this, maybe make the jumps get more thin, and possibly even die from getting too thin.

Cute sound, the first level is actually the hardest to me, that 2nd spike with the water below it is nasty and requires no room for error. Pretty demanding. Stars are based on what was uploaded, not what this game could be,

Also holding space after hitting a water in the air, makes you thin again. I think this is a bug you'll need to fix, where I can't go between thin/thick/thin state unless i touch the ground.

Also, WASD, unless you're adding in a Z/X shoot function.
Curious to see if you take this concept further. ^_^

An interesting concept, but it hasn't been pulled off too well. The music takes some time before playing and it lacks a main menu, sound effects, player feedback, etc.
However I feel that this concept has a lot of potential, you could definitely expand on this.