Long lens needed

So I took the tripod, but didn't have anywhere to put it, without taking up four seats and annoying the hell out of the other doting parents.
Ended up holding the camera, trying not to breathe. Tried to fire the shots in time with the music, when it was loudest, too.
I was sat upstairs in the balcony, about 20 metres away.
One day I will be able to afford the £1000+ required for a proper IS lens. Until then, grainy and blurry will define my efforts.