glitchy
Unfortunately, this had really poor programming, especially when it came to the sprites of the main character.
He starts running in mid air when pressing a direction during a jump, he always turns to face the right when jumping if you aren't pressing left, those crates are glitchy as hell, if you jump into an area with a ceiling right above the floor he maintains his jumping sprite until you stop stop moving, and when you jump against a wall the screen shakes because he's moving in and out quickly, yet it only does it when moving to the right and not to the left.
When making a game, one of your top priorities should be making the player's movements glitch free, considering it's what they'll have to look at the entire time.