This is a very fun little rage monster of a platformer! The graphics, while simple, are great, giving just the right atmosphere while not cluttering the levels themselves. I also really appreciated the small animations in both the title screen as well as the backdrops of the levels. That added quite a bit of life to the game that I really appreciated.
I think my only real complaint with the game is the movement of the camera when the player changes directions. It’s very abrupt and moves across a comparatively large area for the movement involved. I often briefly lost track of where I was focusing on the map simply because I wanted to move a pixel or two backwards while lining up for a tricky jump. I think if this camera movement was significantly reduced, or the timing was adjusted (or both), it would make things a lot less jarring when changing directions.
Beyond that, there’s really nothing I can say that’s particularly an issue and not just a function of the “rage-inducing” nature of the game :)
Over all, given that you say you only started with, not just the engine, but coding only about a week before the jam, I’m extremely impressed with this game! Wonderful job!