I got a text yesterday evening offering me the vaccine and immediately booked in for 9:30 this morning (every other slot was Thursday onwards).
When I got there, there was some confusion, the lady said that under 40s were meant to be coming in from next Thursday, but she'd check if they had enough Pfizer. They did thankfully.
They had 2 queues, one for AZ and one for Pfizer. The whole thing was quick and painless, had to sit in a waiting area for 15 mins after the injection before I could leave. At present I have no discomfort on my arm, couldn't even tell you where exactly on my arm the needle went in.
Side effects wise, nothing of note so far, maybe a little tired but I only got about 6h last night so could be that. I'm drinking lots of water as I've heard the side effects can be compared to that of a hangover.