What Is The Treatment For Soreness And Cyst In The Vagina?

I was fine yesterday, I live in Yokosuka , Japan. I felt ok this morning but as the day went own. I felt a knot/sm cysts at the bottom of my vagina opening. I notice it is sore in that area after urinating. I tried to clean the area with Tucks and put vaginal itching cream in the area but it is getting worse. I am going to try a hot cloth next. What do you advise I do next?