Worried about miss Jazzi

I have been feeling pretty stressed here lately. Our cat Jasmine is not feeling well. Months ago we had taken her to the vet for a concern I had. She was loosing hair around her feet and her once lustrous coat was turning a white to a stormy gray. Our good vet assured me it was probably just shedding and I had nothing to worry about. Although part of me, a big part wondered what the "real" cause was. At this same visit we had our other cat being examined for a skin condition that I thought to be related. weeks later after a shot, antibiotics, and creams the skin infection on Spooky was not getting much better. I asked the vet office again and they said to wait a little longer despite it looking a little worse than before. finally several weeks later she cleared up. Now Jasmine continued having the hair loss. Not a bunch, but a little thinned out around her toes. But now it has grown much worse than that. In just a matter less than a week she has lost all hair around her two feet. She has developed crust's all on the edges of her ears and has two spots on her body that look like infected scrapes. During the first visit months before I feared the worst. Ringworm was seemingly a strong indicator. And with all the evidence I surfaced I had already written the full story. But wonderfully I was assured it was certainly not ringworm. But now looking at our poor Jasmine cat I have doubts and wonder if that was what once was bothering Spooky has jumped on over to Jas.
To all of this I have an entire week until the vet can see her. A time that seems unbearable to the poor girl. I wish I could remedy. But I am also feeling like the worst cat mom around. What to do when I have been so busy the last week with my Christmas and new years that I didn't spend much time loving on the kitties and making sure they were well? For that I feel horrible. Like I neglected my baby. So now as I am waiting, I feel the urge to 'find' the cure. While feeling totally responsible for her condition and without answers. Is it an allergy? A fungus? An Infection? Poor diet? These are the questions that roll in my head. today just before making dinner after I had put away the groceries. I sprayed a product called fung-a-way on the spot on her neck and ears. It's been made for horses, dogs, and cats. Simply, a simple effort, to aid her during the wait. Having never used it before I am curious if it could even' cure her'. But if it at least slows what ever ails her I would be happy. She seems to be so miserable and not herself.
So as I wait I will follow up with how she progresses in the hope and prayer of her getting better. And her siblings staying healthy as well. If you have any ideas or thoughts of what this could be. Be sure to let me know. Until the Tuesday the 11th appoinment I will be trying the fung-a-way. And hopefully the vet office will get some cancellations so they can get her in sooner.