[At this point I'm guessing, but my guesses tend to be reliable. I don't think a few drops will cause you any trouble. And I think you would need to be dead before it became a problem in any case. The ideal condition seems to be completely exsanguinated but otherwise relatively intact. I've never heard of a living, uninjured person being fed vampire blood and turning from it, or for that matter of someone's midnight snack getting their teeth in and waking up three days later. All instances of turning seem to involve someone's deliberate effort, and more blood than you are likely to accidentally ingest. I'd even venture to say that it's not cumulative: if you get a little here and a little there over the course of your Slaying career, and have a heart attack when you're ninety, you won't end up a wrinkled little bloodsucker.]