Yuuri, the doggo likes you, calm down.
( 1/2 ) Well I don't think he lost his toe at all, and since he can walk just fine everyone else knows that too. But I also think the reason he goes over the top with the story is because it ALMOST happened and it freaked Derek out, and Stiles didn't like that. He worries for Derek, okay? Stiles came to save Derek so of course Derek will think it's HIS fault, and this was not Derek's fault, and Stiles' fine!