[He frowns. Goodness, why is it so hard for this girl to own up to a mistake? It's not even that big a deal!! He's not even mad, really. Irritated, maybe, but-- wait okay why is she trailing off like that.]

All actions have an equivalently opposite reaction. Even those with the best balance will waver a little when struck. I did manage to stay on my feet, but I suppose this much is irrelevant. [He's just talking about it because who knows.] Is...there a problem?