I showed up the next day, first thing in the morning, and after waiting for half an hour, I got to see the nurse. She started by asking me where my urine sample was.
Not only had the quack forgotten to tell me that I needed to piss in a cup as soon as I woke up, but he also forgot to give me a cup to piss in, and stuffed the times up by telling me not to eat for 12 hours before the test. The nurse told me to eat nothing after midnight, and to come back the following day.
I now have a small hole in one arm, and I managed to shoot straight this morning. I'll know in two days whether it was just a momentary blip in my otherwise normally healthy existence, or if I am showing signs of wear and decline.