I need some advice, I've done something silly! I seem to have let a weird animal into my building?→[More:]Just got home and found, to my annoyance, that the front door to my building was kept open.

My neighbors downstairs do this (it has a weird built-in doorstop for when you're moving stuff in and out) because one of our other neighbors smokes inside and they are trying to both air out the common stairwell/hallways, as well as to make a point.

So anyway, I come home, the front door is WIDE open (not safe!). Granted, our individual apartments are locked, but as I came in I had to wonder if I would find a hobo sleeping in my (second floor) hallway. So I shut the door behind me, and as I'm going up the stairs I hear a noise down there. I turn around and see something darting through the darkness. I can't tell what it is. The light on my floor was on, but nothing down there. So I scoot into my apartment and lock my door behind me. Then I start hearing something running and making a big THUD noise against the front door. It's an animal. No kitty/dog noises. I suspect a raccoon. They're nosy like that.

So what do I do? Leave it there for my poor neighbors to deal with when they leave for work in the morning? I heard more noises, which means it could have come up to my floor or even onwards to the floor above me...my upstairs neighbors tend to come in late. That'd be a shitty surprise, right?

Suggestions? I really just want to do my dishes and go to bed. But I don't think I'll be able to sleep with this mess unresolved...