From what you are telling me, a cat must have bitten you. And even though it didn't bleed, you saw a burning sensation and a red dot after the event. This is a possible result of bacteria from the cat's mouth. It is important to wash the area with soap and water. Check for any swelling, pain, or redness. If you see anything out of the ordinary, don't hesitate to see a doctor.

The numerous factors that lead to skin allergies on the backside and legs include irritants, allergenic agents, infection or autoimmune disorders. It is necessary to consult a dermatologist that will conduct sufficiently comprehensive evaluation and suggest adequate options for treatment. Self-diagnosis and self treatment can make the situation only worse complicating it.

Without a proper evaluation and diagnosis, I can't say. But normally, suggested treatments for perical pigmentation include topical medications and laser treatments and I do not recommend flutivate cream for pigmentation. However, based on your individual condition, the doctor will recommend the best treatment for you. 

Sometimes not having enough vitamin D3 can cause people to lose their hair. You should keep taking the vitamin D supplement as the doctor told you. You should try to eat more foods that have iron and protein in them as well. One thing that might help is finding ways to relax when you are stressed. 

Pigmentation is triggered by different factors such as genetics, sun exposure, and hormonal changes. A balanced diet rich in antioxidants and drinking a lot of water may help improve skin health. You should consult a dermatologist for proper diagnosis and treatment. They may prescribe an appropriate medication and recommend certain lifestyle changes to control pigmentation.
 

To understand the severity physical diagnosis is important. Based on that I can recommend treatments like medication, laser treatments or chemical peels etc.

Hi , pimple marks can be treated by using topical creams containing retinoids, vitamin C or glycolic acids . One should also strive to follow a good skincare regimen and not squeeze their pimples. If the scars are deep, one should consider seeking medical attention from a dermatologist specialized in treating skin conditions.