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Can you attach the photos here? Pain or itch? Abnormal vaginal discharge?
I can't identify it. Can you circle the indentation on the image with a sharpie or something?
Ulcers associated with syphilis, LGV (lymphogranuloma venereum), and granuloma inguinale are usually painless. Did you have tests for them? How tall are you? How much do you weigh? Any weight change? When did you notice it? Any discharge from it? Is it getting worse? Any other symptoms? Are you aware of anything which might have triggered it? Any medical problems? Any surgeries? Any medications? Any family medical history? Do you use condoms?
They are curable. If it is herpes, it is painful. Did you shave there?
Lymphogranuloma venereum (LGV) is typically found in areas of East and West Africa, India, parts of Southeast Asia, and the Caribbean. This infection has rarely been reported in resource-rich countries, except in the context of localized outbreaks that were reported among men who have sex with men in urban areas in North America and Europe (eg, New York, Amsterdam, London). Granuloma inguinale, an uncommon infection caused by K. granulomatis, has been recognized in parts of India, Papua New Guinea, the Caribbean, southern Africa, and central Australia. They are very less likely in the US. Genital ulcers may also be caused by noninfectious etiologies including fixed drug reactions such as minocycline, Behçet's syndrome, neoplasms, and trauma. You noticed it 5 weeks ago. You should apply antibiotics such as neosporin for a while. If it is not healing, you should see a dermatologist to have exam.
Around 1 month.