Honestly, what you need is a different psychiatrist. Just because the current one is unhelpful doesn't mean they all are.
You could probably use an online test to satisfy your own curiosity, but it wouldn't be medically valid -- i.e., it wouldn't get you access to any kind of treatment through your insurance, the schools, etc.
I would also caution you a little against picking a diagnosis and then seeing if it fits. That's basically driving the diagnostic car in reverse. Who knows, she could have something rare that most people don't know about. And if you start with a new psychiatrist, it's better to go in with a clean slate -- say, these are the symptoms, what do they mean? If the psychiatrist is biased by a conclusion you've drawn (rightly or wrongly) it muddies the diagnostic waters.