Nice idea ! I like the general concept, and the polish (art, different enemies, number of weapons with a different gameplay ...) is incredibly good !
The difficulty curve is a bit tedious : the rooms are not that big so it's quite hard to maneuver and avoid enemies. I have no problem with a difficult game, but some situations felt quite unfair because I was just stuck in a small corrider with enemies coming towards me ^^'.
I really didn't enjoy the music ^^". Waaaaaay too loud, and... Not my genre.
Overall, that's a really good entry, just need a bit more tuning and level design, but I had a blast playing it ! Congratulations !