I would avoid trying to label a hurting teenager. When we label kids we tend to get what we label them with. They can detect our attitude towards them. I'm not saying that she shouldn't receive testing necessarily, but all caregivers should look at her as a good loving child. I have no kids of my own.. so take my opinion worth a grain of salt, but my dad always thought my brother would be a failure and so thats all he saw in him. My brother is now on drugs. I believe in self-fullfilling prophesies, not in a mysterious way but b/c what I think of you, determines how I treat you. and How I treat you, determines how you will be inclined to act. See the link? Even just knowing that my father and grandfather were sociopaths (or at least people thought they were) would cause me great pain as a 14 year old child!! Just think if that were you. Ugh. I'd feel hopeless.
I pray for you to have wisdom in the best way to deal with the situation.

EV