Hint: don’t die.
You don’t say!
The sudden change of rooms was a bit confusing and, against your the hint, i almost always died.
At first i thought the enemies were “dodging” my bullets all the time because the graphics for they death look so much like when i dodge, but i guess this is just because of time limitations.
If i were to continue this game, i think the only things i would change is remove the right button to aim, just aim where the mouse cursor is, and add a hint of were the guys will appear in the new root moments before the change — translucent shapes or something like that.
The rest was well done.