"No--" Tony tried to interrupt, but didn't know what to say for himself. It had been a shitty thing to say, he already knew that. Steve didn't have to dwell on it, and he definitely shouldn't think he had to keep shit like this to himself in the future. He waited long enough to tell someone this time. Tony had to stop, raising a hand to pass over his face only to rest his armored knuckles against his helmet, eyes closed in frustration. "Don't say that," was all Tony could come up with, and to make up for his inadequacy he passed a metal hand down Steve's numbed back, neither of them feeling anything. That was probably better. "Stay still," he instructed out loud this time, for something to say that wasn't fucked up, before extracting the final piece from Steve's back.