This would be a different problem than the leg burning problem, which sounds like peripheral neuropathy.
Prolapse of the pelvic floor should be attended by a gynaecologist. Till then, you can try with Kegel exercises which can be done at home.
LinkThe blackening of the skin could be due to a number of causes including continuing fungal infection, overuse of steroids, etc. Do not apply any more ointment to this area and instead massage daily with moisturisers.
I would advise you not to go too much for self treatment and instead consult a doctor for this. You need not go looking for specialists and instead consult a family physician, who will be able to diagnose your symptoms very well.
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