Good atmosphere, funny texture differences
Your use of silence was excellent, "Signs" used that effect similarily.
The image of the head and the hanging body was disturbing enough, it didn't need to have a screaming blare behind it, so good thinking avoiding that.
Unlike alot of the people on this site, I don't understand flash animation very well, other than to say what seems good, and what seems bad, but from a technical standpoint, I don't understand all the code, although I can tell from all the 3-D, this must have been hard to do. So my score of 7/10 isn't based on flash, but on mood and story. And the reason I am only giving it a 7 out of 10 for those reasons is because I flt the mood didnt match the graphics very well. The main character is undeniably cartoony, where as the environment he occupies and the dead bod had an eerie realism.
Things like the toilet and the shower curtain, with a complete lack of texture, looked funny against hihgly textured walls. This took away from the mood in my opinion. But still, it was quite good, and I was still feeling quite tense depsite this minor nag of mine.
Great Work!!