I had about a red bump that got to be about Nickle size right along my panty line like a this. It swelled up and was raised up about a Quarter inch. Very painful for a couple days. And Very Scary. I poked it when I saw a whitehead form it drained like a pimple including bloody looking liquid too. It did this for a couple days. It went down and wasn't as painful. But still red, big and painful. It scared me enough to go see the dermatologist. He said it is basically a pimple and had a big name for it. He said not to worry, nothing horrible, that many people get these in this area a lot. He said to keep the area clean, which I do, but it happens to people anyway. Mine was infected at this point. He prescribed Cephalexin twice daily for 7 days. Just started antibiotics this morning, by tonight when I took the second dose it has decreased the redness already and soreness. I will be taking the full course of antibiotics, to totally heal this and keep infection from coming back. Hope this helps. I have been using neosporin and a bandaid and will continue that until it heals. Doc says that is a good idea.
I'm only 13 but when I was about 9 I had welts all over my body that were really itchy and sore. Is it similar? The doctors told me it was a hormonal reaction and some people have it all their life, but mine stopped after 2 years. If not then maybe its a reaction to your underwaer :S like the washing powder they're cleaned with or maybe the fabric is irritating your skin? Just trying to help :)
Harriet