Pretty nice! But very hard to control with a Qwerty keyboard until I found that I could also use the arrow keys. You should put it in the game somewhere that you can also move with the arrow keys!
This game really messes with my sense of orientation haha. It took me a long time to understand that everything was random. Even if you exit through a door and go back again through the same door it's not the same level. I think it works well with the design of the game. But you should disable doors next to the player's starting position. I was able to get to the boss without defeating any enemy by just staying near the left door and pressing "E" to enter it as soon as I gained control. This basically allows you to reach the boss room without having to play any of the game before it! But as I said, it would be simple to solve: simply make the door that the player came through closed and prevent the player to go through it. I know this was intentional, but the boss wasn't hard enough to make me need better gear to win: you can win as soon as you start. Maybe you could also make the boss unable to be defeated until you found a certain item, like him having a magic barrier that only goes away with a magic sword or something. That way you can keep the mechanic of you being able to skip rooms, but you make it so that the player needs to explore a bit or they may be screwed when you get to the boss. It's not a perfect solution, but as it stands you can basically skip the entire dungeon. Either that or make the boss MUCH harder and the power-ups much more effective.
That said, I enjoyed the game. It's pretty well made for a first game, too! Well done :)