This is what I was thinking when I wrote the story, (or any story I have ever written, or might write): The book is not finished until you read it. I mean, you, the reader, not me, the writer. It doesn't matter whether I think the boy was a werewolf or just imagining being one. Once I am done with the writing, and the book is printed, and in your hands, it is yours as much as mine--and what matters is what you think. So, both ideas can be correct, and you can even make up more of the story in your heads, or write it down and make a whole other story. If you are thinking about it, it's your story now. I hope you have fun with it.