You are right, it could be either. Often, though, people think they cannot sleep when they really are. We don't actually know why this is. I would check on her at night and see if you can tell if she is sleeping, in other words, in her dark room, go up as close as you can, listen for her breathing and see if she notices you. If she doesn't, she is prob. asleep. If she says, "Why are you in here?" you know she is indeed awake. Take her to a primary care doctor and get labs drawn. Insomnia is a very common human problem. Stress, schoolwork, peer pressure, family problems, so many things can contribute to insomnia in both youths & adults. If primary care cannot find anything physically wrong, after tests and physical exam, take her to a child & adolescent psychiatrist. You must find a specialist. Psychiatry is broken into several sub-specialties, child & adolescent is one of them. Adult & adolescent starts at age 13, so she needs a child-trained psychiatrist. This involves 1 extra year of training. Regular psychiatry training is 4 years, after one finishes med school. It is good you care, she tells you what is going on & you are looking into answers.