Suggest Treatment For Red, Painful, Flaky, Itchy Rashes In Pubic Area

I have had a red, painful, flaky, and itchy rash in my pubic area since around September. I have psoriasis and I have to wear adult briefs to bed. at first I thought it was my psoriasis or diaper rash, but neither have lasted this long in the past. It started in my inner thighs, but recently yellow bumps began forming one my pubic area. It's really painful and effecting my work. Please help, I'm really scared.