A pause menu would have been a good idea, I'll have to work on that next time I do a jam, thanks!
There is no key for rewinding, it's a sort of replacement for your health-system. You can actually jump right onto the boxes in level 3, and the infinite pit is a mistake I will fix shortly... :p
Added a coin sound effect too, hope it's alright!
I liked your game as well, the sound effects made it quite satisfying to play, although it was hard to know that I had to deliver the tapes to shelves that were not on the screen.