I still wouldn't lay it down because it could be QQ or AKs or even AQs or something at this limit.

I often find myself saying "bleh i know it, he has AA" and then he shows it down and i get mad at myself for not folding when i "knew" he had it. The fact is though, that its just pessimism. Since its' the only hand that can beat you it's the only hand that you're afraid of and therefore the hand that you begin to suspect.

It is very obvious that its a strong hand though, but not 100% concrete enough for me to lay down KK.