I am sorry to hear you are worried about Tripper. My name is Rebecca. I am a veterinarian and will do my best to help.
I just came online and saw your question. How is she doing now?
Can you take her temperature with a thermometer?
If you check her gums, are they pink or pale?
The hair loss may or may not be related to her not eating. If I could, I would check her for dehydration, take her temp, listen to her with a stethoscope, palpate her lymph nodes and internal organs, and try to figure out why she is not eating. I am glad you got the tuna water into her. Since she is taking that, I would try to get her to take some food.
This could be an infection, pain from the skin problem, internal illness causing the skin problem. If she is not eating soon, she should be checked out by your veterinarian.
Let me know what other questions you have. Rebecca