What Causes Pain In Vagina During Sex?

hi. me and my girlfriend have been having sex for about 5 months, but just recently she has been having alot of pain in and outside of her vaginia when i finger her and it hurts more when i put my penis in. today we tried it and her vaginia was hot and red we have tried a chlyamidia test and a thrush test which has come back normal on both, please can u help?