I'll concur with gness about the noise - it was a shocker.
There's nothing inherently wrong with very loud rock/pop music - if it's decently reproduced and in the right venue.
We saw The Illegal Eagles a while ago and I'd bet that (on a pure decibel scale) they were every bit as loud as last night's disco. But the sound quality/balance was impeccable and we were in a biggish theatre with great acoustics - my ears were not ringing even after the best part of three hours.
Last night was a small pub room, the music was horribly distorted (all treble and crash sounds) and my ears said "you need to leave now before real damage is done" after less than three minutes - let alone three hours.
Even hiding at the very far end of the pub, around a corner from the bar area, it was simply painful to listen to - the DJ couldn't see the problem - but then he was comfortably inside his headphones all night whilst he damaged everyone else's hearing...