Until I managed to leave the house I was worrying that something would happen to impede my progress, after the fifteen or so months of successfully not catching anything before getting vaccinated. It wasn't clear whether the appointment time was the minute at which the physical delivery of the vaccination would occur, or when they wanted you arriving at the building, or when you were expected to be going through the doors after any queue worked its way through. There was no queue when I arrived, so I entered the building about three minutes ahead of time after all the usual double-checking bike locks. There was a wee wait at the check-in desk where you give the number, then another at the first set of queue-booths before the actual delivery. They correctly identified the lesser risk of travelling by bicycle and recommended I wait only five minutes in the waiting-zone. If it were busy it would have been quite perturbing, perspex screens notwithstanding, as it's all in the underground conference room which I know from experiences at work events to be insufficiently-ventilated when packed with people. With the seats down, lights up and no blaring music it was quite spacious, but there were lots of booths.
I had what was possibly a small headache later in the afternoon, but could equally have been due to normal things. Slight achiness and a detectable injection spot the following morning, which I definitely prefer to no indication that anything is happening.