How To Cure Red, Dry And Itchy Vagina?

My vagina is red, dry, and itchy . Me and my boyfriend had sex with a condom but we took it off and finished having sex but my vagina was dry and he went back in dry does that have to do with why its red, dry and itchy? He has been tested for std s sti s and everything and he s clean. This itchyness is very uncomfortable. I m not use to being this dry. I can t tell my mom about it because she doesn t know I have sex. Please help I m very worried