Is this supposed to happen?

This is after the fifth dream, I've invaded the Iron Throne tower in Baldur's gate and I find that My main character goes insane whenever a fight starts and proceeds to attack enemies and then allies. I lose control of him and cannot cast any spells using him.

I have removed all equipment from him in an effort to undo any curse. but he goes into a confusion style frenzy even when naked.

Is this supposed to happen or did I do something to my character?