What is the appropriate response if he does it again? I was so stunned it took me a minute to even realise what he'd done - and it bloody hurt.
I told him in a stern voice (loud but not a shout) that biting is not nice and not on, and placed him on the other sofa away from me, after a minute or so he got down and came to me so I cuddled him, and that was that.
I know he is very young so I'm not after discipline tips or anything, I just don't know the best way to respond.