You cannot rule out ringworm based on appearance only. Ringworm manifests in a different way in cats from people. Dietary allergies, behaviour anxieties, parasites, hormone diseases are some of the causes and there is no way an opinion over by internet will help in this case. Your cat will need an exam, possibly a skin scrape and microscopic exam and a biopsy may need to be considered also. Your vet will need to guide you based on the clincial exam. Sorry I cannot be of greater help but good luck with trying to diagnose the condition and treating it.
Martin Slome DVM
Centre Street Animal Hospital
7700 Bathurst Street Units, 40-42
Tel. (905) 771-9855