Cool entry!
The idea of pressing a button quickly with your mouse seems like an interesting concept for a platformer like this.
In terms of feedback:
The speed of the character is a bit high, in my opinion, which can be fine if the game is designed around it. In this case, I don't really feel like I'm ever fully in control. There's a bit too much gravity, so jumps feel very quick and difficult to control. Overall, I don't think I'd have a problem with this game feel if maybe you popped the camera back a bit, maybe gave it some damping so it didn't follow you perfectly and instantly, and maybe stopped it from going past certain coordinates in the level. It can be a bit disorienting for it to follow your character perfectly while you jump since jumps are so quick.
I think the gaps where you have to crouch aren't really too evident. You can only know they're there because you can't move past otherwise.
You could maybe recreate your levels using tilemaps, it feels a bit odd to have ground tiles used as objects since they also have inconsistent sizes and stuff.
The music seems a bit quiet!
Keep up the good work!