Swollen perineum !

Hi! This may sound disgusting but I’ve been away camping and used the same pair of thongs for 4 days, yesterday I got an itch in my pernium (idk what it is called but between V and anus) and today I took a look. It it really red and swollen and it’s like a straight line that is swollen where the thong has been. Idk if it is swollen because of the thong but that’s the only cause I could think of. Should I be worried?

I’m not pregnant either and now I took them of and put on some aquaphor