Oh, I'm sorry. I mean like reset my library or something so it goes back to how it was, I guess? I don't exactly know how you'd fix that..
I just checked again and all of the missing songs are in the folder for my library but they are not in the actual Itunes one, if that makes any sense? I never do anything to these folders so I have no idea why it would be like that or what could have caused it to do that. And no, the content was not moved to a new computer.