"I am 100% sure it did not come from me - my nose was not bleeding, and there was no blood at all in my nasal canal - anyway, i was worried bc my nose is a mucous membrane....should i be concerned at all? if the blood happened to be from an hiv positive person, is it possible to be transmitted in such a way? should i schedule testing?2 - skin is a good barrier against transmission, right? (obv. not" . . . .