[quote=Kaga]I realize it's a harmless prank. I just can't see her making that sort of attempt to mess with me.Plus she was there when I acknowledged that it had fallen, at which point if she had been the one that knocked it off then she would've started bursting out laughing cuz yeah she would not be able to keep a straight face through that. So yeah, ruling her out...[/quote]

Alright.

Then the next most probable outcome is probably the wall banging, or maybe your roommate had quest and when he/she wasn't looking one of their guests accidentally knocked it down.