Interesting. Not bad and I really liked where you were going with this. Just a few observations:
Just out of curiosity, why did you rush the production? Was this to be submitted to some contest or something? Seems like a few more takes could have helped the actor reach a bit deeper. I don't know what the production constraints were but I feel like you have something good here and it deserved more time for proper execution.
Plus never hesitate to take the camera in closer - especially on the rants...makes the performance tighter and draws us in. Moving in closer would have helped with the sound in the bathroom scene (as I suspect that your sound is coming from the camera? I could be wrong).
I am not sure if you just used available light (room fixtures - seemed that way to me) but just be mindful of your lighting. The opening scene with the dark door - there's a lot of digital noise and muddiness in the dark/shadows. Don't be afraid to put a fixture there or bounce some light to clean up the picture.
It's not my intent to beat-up on your production because I really do like it. I just feel like it could have had a bit more to it. It seemed rushed. Maybe those were the parameters you had to work in, if so, this is pretty decent. If not, still decent just take some time to add a few more takes to allow the actor to get inside of the character (especially on the psychotic rants) so that the acting is not coming from the surface. Get in closer with some CU and ECUs to really draw us into the story.
Nice work. Keep it up and good luck on your next production.