It cleared up on its own in the end and I'm back home! Thank goodness.
I started getting brain fog and fatigue within minutes rather than later in the day and after half an hour had to get the bus home. After I'd eaten (an hour after the shot), which due to my usual problem usually makes me really tired, I had an adrenaline rush and my heart started racing, which lasted for hours. My pulse was measured at 120 (should have been less than 90). A couple of hours later it was down to 100, then a bit later heart was normal (though still on the high side). Blood test results all normal. I still have brain fog though and I'm a bit achy.
They were confused, as they have no information on this as a possible side effect. I guess I'm a mutant!
Yes, that one. It was created here at Oxford University and we produce it here and have a priority deal, so it's the workhorse of the UK's vaccination drive, though we are also using Pfizer and Moderna.