This is why he doesn't talk to humans; if Aziraphale had caught him flinching, he would've just made a sympathetic face and moved on, not addressed it out loud. Now he has to wave a hand and pretend like it doesn't matter. "S'fine, isn't a big deal."

It very much is a big deal, but he's choosing to ignore it in favor of making a face at Sam. "Alright, alright, no need to look so bloody skeptical." The audacity of this man. Crowley would be super scary! If he wanted to be.