Wow! This was a very fun game actually! Lots of things to love about this game, let me share my thoughts:
1) For a global time rewind centric mechanic, your time-stop controls are very intuitive, smooth and great to use! This is amazing because it lets players to freely play around and glide around with the time stop, and rewind mechanics. Not much comments for the 2D character controller - it works.
2) Simple mechanic and used it to create a few levels to experiment with it. Like!
3) The countdown at the beginning of maps was a good way to let players be first introduced to the level, before letting you go with it. This is such a small - but I believe, very good feature for your game design. Applause!
As short as these comments are - their actual value cannot be described with just words. Especiallty with regards to the first point (1), the fact that you have a polished experience really just helps the gameplay shine - this becomes especially important in platformer games!
For some other comments for possible improvement:
1) Hahaha, I think it goes without saying that the graphics need work. But in jams, we rarely have time anyway. But more specifically - I think you need to show spikes in maybe a red colour, for a clear indicator of death when touching it.
2) Your character's scale changes awkwardly when you stand on platforms - this is a problem I also face in my game, I also have no idea how to fix it. But it's jarring enough to worth mentioning, so here.
3) I think the platforms need a speed limiter - they can occasionally be a bit too fast even for timing when to stop the time. Meaning to say, just implement a max speed in their function. Having such high speed platforms can be a deterrent for more casual playerbase.
But hey, this game was fun to play - and I hope it was fun for you to make. Would love to this expand with some sweet ass music (oops language..), simple cartoon graphics, and some more levels as a fun product. If you do, hit me up!
Cheerios.