I like the shot, however something looks out of place on the door. Maybe someone else on here with a little more experience can tell you what it is, maybe out of focus. The door just seems to be a little grainy/fuzzy to me.
Too much gray for me and like zero highlights. I'd definately try changing the tones (I think people with PS call it curves or something, but I'm not sure) to bring out some highlights.
Whats the theme here? I agree alot of grey. and the door really does look grainy. What ISO? but im not sure thats it. since the door is really the only thing that comes off as fuzzy.