Congrats on finishing your jam game! This is pretty cool!
I love the idea of a platformer that so clearly cares about the number of times you've touched the ground. That's a really cool avenue to explore. You did a really good job of designing your core mechanic and making the implications clear. The cute blobs helps, too :)
I think the level design needed more time or playtesting. Most of the levels felt good enough, but one in particular I found a little unfriendly. The stage with the early paint bucket on optional key platforms. Up until this point, you've taught the player that size equates to health/durability, and that size should be preserved. However, this level actively punishes you, to the point of needing to be restarted, and it's not that short. The level provides the player opportunities to preserve size, but upon reaching the end, you realize you need to be small AND have laid a return path for yourself. Meaning, if you've reached the end and have learned the above, you've now made the level extremely difficult and more tedious. That's just not fun. It felt like getting punished for not knowing what's at the end of the stage, without having a way to know what's there. This sort of twist or wrinkle to a puzzle is common, but is much more effective when the cost to repeat the stage with the new knowledge is relatively lower.
I hope all that rambling makes sense!
Still a super cool concept and I thoroughly enjoyed my time with it. You did a nice job with the controls - ensuring the player had precise control while grounded is really important when the individual tiles touched are so important. I felt clever when I could be large and only balance a small bit of myself on a platform to preserve size.
Great job on your submission! Keep making games!