Rash on inner thigh and scrotum and a suspicious lump/ball on skin. Please help, only 17 years old.

Hi, I've been having this problem for well over a month. I have this rash in between both thighs and scrotum. The rash is worse on my right side. I also have a pea-sized, painless ball on the scrotum (right side). It's not on my actual testicle (hopefully) but I am still very concerned. It originally started as a painful lump a tad bit bigger than a quarter on my actual thigh (inner, right side) that eventually went away. I think the lump and this rash have something to do with each other. The lump never came back, but this rash hasn't gone away and it's been weeks. I found the lump/ball on my scrotum last night. I woke up this morning to check and it was still there. My general doctor (who I saw before this lump/ball appeared) said it was due to heat, but this is highly unlikely because I'm always in my house and it's never hot. The only thing I've tried is triple antibiotic and it has not made a difference. There have been days where the rash disappears, but it eventually comes back. I really need help because I suffer from anxiety and this is making me very uneasy. Any help would be highly appreciated. I would post a picture for more detail but I'm a minor and that would feel awkward for me..