A neat little puzzle game!
The levels you had were good, but since it's such a short game the difficulty curve seems a little steep. After the tutorial you jump right into a puzzle and have to think a bit. Maybe you could have made puzzles that teach the player everything they need to know? All the interesting things you can do with the rewind ability. Your tutorial is fine, though. I think it would make for a smoother experience if you slowly transition into the game, but a 2 minute tutorial does also suffice.
One thing that bothered me was that I couldn't tell which pressure plate opens which door, so you had to figure out first what each plate does. Maybe you could have given them symbols as well?
Definitely one of the better games!