I enjoyed your game.
I like your art, it's way better than what i can manage.
I also like that most actions have animations, sound effects, particles, etc. Feels juicy.
Movement mechanics are solid and satisfying.
The only thing that significantly reduces the enjoyment of the game is lag, it's really bad, you should figure out what is causing it. (It's rendering the entire tilemap each frame probably)
Feedback:
1. Fix the FPS issue, please, this shouldn't lag that bad.
2. It would be nice to control the dash strength so you could do a variable strength dash.
3. Add branches to your level that have unique challenges filled with collectibles.