Very interesting mechanic, that's a really good idea ! One of the most difficult part of the jam, I think, was to find a way to show the player what is real and what is not without relying on the frustrating "trial and error", and you nailed that part perfectly !
Overall the game is great, the controls, feeling and art style are very good and it was really enjoyable ! My only complain would be the lack of checkpoints, I didn't finished the game yet because I died a couple of times and it was frustrating xD. I'll give it another shot later ^^ !
Congratulations, that's a solid entry ^^ !