From experience all I can say is: just don’t give a f…!
I always held back when performing because I was too afraid it could go wrong but in the end nobody would know because you’re the only one who knows how it’s supposed to sound. And the best performances are when you just forget everything around you and just let loose meaning truly expressing yourself.
Everything else are just obstacles that you put there yourself (besides technical problems that are out of your reach maybe) and that will prevent you from achieving it. I‘ve seen so many shows in my career and that I would consider „meh“ from a performance aspect but people had a good time.
One band for example came way too late for setup and soundcheck because they were stuck in a traffic jam. Like really late, maybe an hour left before doors opened so they set up quickly and did a quick soundcheck and told us before the show that they would maybe play for an hour max because they were all exhausted (they came by car from Poland) and in need of sleep. Well, they played for almost two hours because they just got into the zone and forgot everything that was troubling them and you could feel the energy coming from the stage. Afterwards they appologized and gave everyone of the staff a CD of their latest release with a big smile on their face. Those are the kind of shows that stick with everyone involved.