Sherlock wasn't exactly answering his question, but then he wouldn't have expected anything less of him. John could see that he was in a bit of pain, but at least there was no obvious damage- no pools of blood or missing limbs, and considering what the train liked to throw at them, he would take that as a good sign.
"I know we are, I know- it's all okay," he told him, not sure whether he was trying to convince Sherlock or himself. He let Sherlock hold onto him, and carefully guided them back across the wreckage out onto the open beach. "It's okay- let's just get to safety ourselves, and then we'll worry about everyone else," he told him. It was quite a change from the soldier who would have risked everything to save complete strangers with absolutely no concern about laying down his own life. But things had changed- Sherlock was always going to be his priority, now.
Once they had put a good distance between them and the wreck, John brought them to a stop. "Come and sit down and let me take a look at you," he said softly, nodding for him to sit.