I've noticed that the skin on the right side between my vagina and anus feels hard, almost like there's a lump under the skin. It's quite painful, and I'm really concerned. I'm wondering if this could be something harmful?

This could be due to a condition called a Bartholin's cyst or abscess. I recommend using sitz baths to help reduce the pain and swelling. You can also take over-the-counter pain relievers like ibuprofen. However, if the pain persists or worsens, it is important to see a doctor for further evaluation and treatment. In some cases, antibiotics or drainage of the cyst may be necessary.