Chameleons do better in tall screen cages. They need maximum airflow. Get ride of the bark, it does no good to keep it in there. It can just cause more harm.
If you find out how old she is, tell me. My friend has a chameleon who has only shed once in a month, but when I had my Cham as a baby he sheded around once a week. For now I would recommend that you keep an eye on her. If this continues take her to an expert.
I have not had health problems with my chameleon where I have had to take him to the vet. I don't think I can help with vet recommendations. I hope he starts feeling better. What are his living conditions?
When I got my baby male he started hissing to, but he was always hungry. She might just be super stressed. If this continues I would take her to the vet. Has she shed yet?