That's because that's a normal reaction to trauma, Fenris.

Klaus is pleased, though -- at least he's broken through the seriousness by confusing the shit out of the other guy, and now he just has to desperately grasp at another thread of conversation to veer them wildly off course.

"Like I said. Don't worry about it." And then, because he does need to make another line of conversation happen, "How's your head? Still jackhammering?"

He does have an actual halfway decent cure for that that isn't wildly sexual.