Vaginal Itching ? For The Last 3 Days My Vagina

Vaginal itching ? For the last 3 days my vagina has been itching and I first noticed it after I had sexual intercourse with my boyfriend . He is the only one I have ever had sex with. I scratched it and it began to burn when I pee, but I believe the burning is gone . Now my discharge is not normal, instead of being liquid and sticky , it is mushy like wet toilet paper & it is an off-white color . What could be wrong ?