Interesting. This would fit with all the stories of his rages about having his eggs just right when coming back in from shooting p(h)easants etc.
The initial reaction is just on the 'fair enough' side of irritation when you're constantly in the public gaze, probably short on sleep, high on anxiety etc. People don't expect the King to be wandering around with ink-stained hands.
It's the second phase reaction, a few seconds later, that is the most interesting/worrying bit however. A flash of nasty petulance which all around him at the time pretend isn't happening (which signals loud and clear he has been like this often).
The only consolation would seem to be its impotence - it isn't directed at anyone in particular and seems to be fizzling out as he exits shot.
Instantly made me think of a lost little boy, desperate for someone to really listen to him. I blame the Gordonstoun of the '60s/whoever it was who sent him there (I'm only half joking).