Had my spring Covid booster vaccination on Thursday, Pfizer which was what I had last two jabs. Blood sugar didn't drop initially afterwards, as they did with every other vaccination, but shot through the roof and am needing more insulin than with previous jabs. All that's beside the point really, the totally unexpected thing that happened is that I got up to the loo during the night and collapsed. Seem to remember this happened to you @Fairygodmother, following a jab. Thankfully, am bruised and exceptionally tired, but otherwise ok. Bloods weren't low at the time, so am putting it down to the jab.