The artwork is nice. The music isn't bad. The second portion was much more difficult to get through than the later portions, but that's normal for a game jam. Here's some thing you may want to look into if you make another platformer or similar game:
- The camera doesn't need to follow the character at all times. I would recommend either of 2 methods: 1. not letting the camera move up until the character is on a platform, then moving the camera up to match the new platform, and not letting the camera move down until the character is below a certain point on the screen, or 2. not letting the camera move up or down until the character is outside of a center area with height just a little more than the character's maximum jump height. Either of those methods will stabilize the camera enough so that ground and ceiling don't constantly go in and out of view
- Having a single consistent jump height tends to not feel very good. It's better to find some way to let the player control the jump height within a minimum and maximum (with the minimum being high enough to not feel like the character is being pulled down immediately). I typically prefer to do this by having a downward acceleration due to gravity along with a second downward acceleration theoretically due to drag whenever the player is moving upward but not holding down the jump button. I've noticed more recent mario games tend to have a more linear jump though, with releasing the button being what causes gravity to set in at all (paired with having a maximum fall speed equal to the jump speed)
- Doing the exact same jump repeated will get boring very quickly to anyone who plays platformers a lot. Even if it's just to fill in a vertical climb, it's better to vary the relative positions of your platforms more.
- You can get away with a lot by slowing down the animations of a 2d character.