Not too bad
I didn't really lose interest while playing it; blood and gore usually keep me entertained. However, this could have been a lot more original (the continuous dead people and codes got repetitive) and should probably include grabable items and maybe an ending, one that should obviously include the killer :) Aside from that, a nice first effort! If it were longer, I would have continued.
Also, one more thing. When you go to click on the wall that "closed behind you" and you need to enter a code, I found out that if you don't know or remember the code that there's no back button to get out of it. You have to X out of the game entirely and start over. You may want to fix this.