Lisa Himmelfarb was a great help to my child, and with her help, we were able to "stop" anorexia in its tracks. My DS was severely calorie-restricting and limiting the types of food eaten and generally becoming very food anxious. Though weight was still within "normal" range, DS had fallen off the historic weight trend (though his height had increased significantly), was teetering on the edge of underweight, and was experiencing fatigue, lack of energy, and general anxiety. I had noticed that he was acting strangely about food but didn't really become alarmed until he confided that something was wrong. Then I was alarmed. DS began to see Lisa weekly, and she referred us to a nutritionist, Elizabeth Davenport, who was also extremely helpful.
http://www.lisahimmelfarb.com/
https://www.pinneydavenport.com/
Unfortunately, neither of them take insurance.
I think you should have your DD evaluated if you are worried about this. My sense is that things are likely to be worse than you think, not better. Start with your pediatrician, because any specialist or therapist will want your DD's height & weight trends and a medical evaluation. Our pediatrician was helpful and supportive, but eager to hand us off to a specialist I think. This is really not their area of expertise.
This website has a lot of good information:
http://www.feast-ed.org/
And this is the related discussion forum, which I found both terrifying and helpful:
https://www.aroundthedinnertable.org/?forum=136439#gsc.tab=0
My son made huge progress both weight-wise and mental-health-wise over a period of several months. He's gained 25 pounds over the past year.

FWIW, he does continue to suffer occasionally from some mild anxiety. He is managing well with self-help techniques (no medication), but it's something we continue to keep an eye on.
Good luck.