Got my booster shot the other day. *shrugs* Same consequence as the other two shots: some soreness at the injection site mainly for the first 24 hours and that's really been all, though I will say that I also experienced a very small amount of extra tiredness for much of the following day. Today I'm feeling totally back to normal. So no big, in other words, especially if you're young enough to be using VGC.
This shot was MUCH easier to get than my first two. I had to chase down the first one back in March and got my second in April more easily, through my employer, but had to schedule an appointment. The booster I got through my employer over my lunch break on a whim. Easy peasy.