Very good but the player is too slow

I had some controls issues at first but finally was able to play. It looks good although I would have loved a more consistent look (pixel art character, clean font, etc). It's a bit simple, it lacks a bit of fun in the controls, and more feedback (the first time I hit a spike I must admit I didn't know what happened, I didn't see it really well, the game just restarted)
But you still completed your game, and that's already something ! keep pushing !

The game looks good and works well, but perhaps the character needs to move faster and more smoothly. It would be nice to have more enemies and maybe even incorporate some attacks or handicaps to make it more interesting to play. These are just some ideas that come to mind to help you, but I can see the effort you've put into it. Congratulations!

the boss fight was somewhat interesting, but other than that I can't really say much about this. The character walks slow and can only jump, and if you die you have to go back to the beginning of the level, which doesn't take that long but because of the player's speed it feels like a slog. And the limitation doesn't impact the gameplay at all. 

I don't want to be completely negative, so I'll just say that if you want to improve for next time you should A. Respect the Player's time (Don't make anything overly slow and don't make them repeat too much of a segment they've already done) and B. Some kind of unique idea behind the game makes even a not too great game at least more interesting than a normal platformer with nothing that different.

I'm sorry about being so negative but I do hope you keep doing game jams, they're pretty fun and stuff!