Really great game my friend! So much fun and intense! It reminds me of the new doom with a top-down approach! Rock music and blood splattering everywhere! Sooo cool. Nice job.
I would recommend you to add more enemies and health packs along the way(or maybe an easy mode where hp regenerates). The rewinding mechanic is not so special, but the idea is nice. Maybe a few improvements would make it better!
Anyway, nice job mate, check my game too!