That stumble was probably Tony's fault, but Mystique did shoot him in the hand so he wasn't sure if they were even or he should be apologizing. Probably apologizing, that always seemed to be the answer, and Tony so never wanted it to be. So he said, "Okay," but watched her expectantly, like he knew if she tried to walk off she would probably fall over and signal, at least, his win in the scuffle. Was that something to be proud of? Hardly. Fuck. He meant to walk slowly after her, keeping his distance until she needed an arm up, but he froze instead. So that was it, he was guilty enough to let a known terrorist just walk out for the fourth time?