Uhm, I see some z fighting here and there (to the end of the tunnel where I picked up the axe).
I actually managed to fall out of the level by crouching in a hole which took me out (from the z-fight spot, turn back, then right).
Graphics is very simple but functional. For this first, short experience, I give you a thumb up.
But consider making your level smaller. Ideally, there should be no "walking around", no "dead times". Ensure your distances are correct. Unless you want to slow down the pace, do not make a corridor longer than it should be.
Not too bad, the animations are fine, not to say they couldn't be improved, but they don't look horrible, just simple.
When you "kick" the doors though, I can just hold q and move them anywhere I want. I can do this from like 20 or so ft away from the door.
There also seems to be a clipping issue with some of the walls. It looks like you might have two walls in the same place and depending on the way you view the wall it sort of leaks through.
I'm not sure if it was your intention, but the area where you walk by and hear the scream, you can keep walking by it and hear the scream. I would've personally just made it a trigger point and have it give a full scream once.
Also, as Krohm said there's the area where you crouch to walk, and fall down through the level. Aside from falling through the level, if I let go of crouch, the player stands up with his head through the ceiling.
All in all, not too bad for a start, but don't be cocky like you kind of were in your title by saying test your "epic" game. You might get a bad reaction with that attitude. Anyway, best of luck with Unity.
Good stuff, quite fun to try out with lots of features like the physics and animation and particle effects and doors. I must have a play with unity myself one day, only hearing good things about it.
As to what's wrong, there's a few minor bugs like I got stuck in the geometry of one of the walls. And fell through the earth when I went through the crouching passage but that looked like it was as far as you'd got on the level, so not really a bug. Also when I went into the interface the mouse still moved the viewpoint, which was a bit confusing.