I quite like how elegant the concept is, as it is immediately clear what is going on. Unfortunately it seems like the time ran out when it comes to level design, but you probably already knew that. Time management comes with experience, so don't worry to much about it. I do suggest it is a mistake to have levels seemingly infinitely loop, as that leaves a worse impression then sending to a static, white text on black, thank you for playing screen. When it comes to the level design that there is, I expect you already had ideas that you weren't able to implement. The simple mechanic of growing alone can make some good straight forward puzzle platform levels. That makes the time spend on the different area effects seem misplaced. I could not figure out what the teal coloured area's effect was, as my body seemed to grow just the same. Also, since most people come from the press-longer-equals-higher-jump tradition, you can expect a player to keep space pressed, which in this game is a detriment. That is something to keep in mind. But take pride in that you did not fall in the trap of most first time developers, and actually have a way to quit your full screen game. You can't imagine how many times I had to use alt+f4. For the next time I suggest already looking before hand in how to export to HTML5. It is not that difficult, although Unity's WebGL has some unique pitfalls, but it helps immensely in the discoverability of your game. With Unity, you need to increase the viewport on itch.io such that the WebGL border is not cut off, and you need to turn off itch's own full-screen button, since it does not work with WebGL.

Very well done on your first game jam, and good luck with any future endeavours.