Just spoken to kate, one of my flatmates. Apparently about 2pm, I came home and spent about 15 minutes violently vomiting. She didn't see me, but she heard me, from the other side of a goddamn fire door. Quote: "It sounded like someone was dying out there."

There were patches of blood around the light switch and on the wall beside and behind the toilet, but she wiped those up (thanks Kate). Presumably it was from the graze on my hand, and I vaguely remember trying to hold myself up while peeing (accurately, I'd like to point out) into the toilet. Apparently there were other patches of blood on the wall of the corridor as well, but they've been cleaned up too (again, thanks). This lends credence to my memories of my Pong-like movement along the corridor.