What is the situation when the external genitalia hurt like they are being stretched by pubic hair?

Patient's question:

Last night, I felt a bit of pain in the external genital area, as if stretching the pubic hair. When I pressed it with my hand, I felt a lump. Whenever I touched that area, it ached a bit, and it didn't seem like just a simple lump causing the pain. Since it's in the area where the pubic hair ends, it's hard to see exactly where the lump is. It's been like this all day—feeling a bit painful and itchy. What could this be? ?? Thank you
First follow-up question: What's the difference between an ulcer and folliculitis? Based on symptoms, what are the differences? Thank you

Doctor's answer:

Hello: Your condition is likely to be related to folliculitis, so it is recommended that you actively go to the hospital for a check-up. At the same time, it is important to pay attention to personal hygiene. Trichomoniasis vulvitis not only affects a woman's life but can also lead to gynecological diseases. Therefore, it is best to go to the gynecology department of the hospital for a check-up, identify the cause, and then receive targeted treatment. Pay attention to personal hygiene and maintain cleanliness in the perineal area.