Any non-nomrmal behaviour, taken to an extreme, can cause a disorder in the sense that that person can't function (e.g. to keep herself fed and employed). This means unless we literally are the most average person, we all have the starts of a disorder. It does not mean we have a disorder because it's the magnitude that makes it a disorder.
Genuine question: in this case, what is in fact the disorder? Reading through the description of Schizoid, they like to be alone, they don't meet people's emotional expectations -- these don't sound like disorders.