What Causes Vaginal Bleeding After Intercourse?

Hi there
I had sex last weekend . during it was quite sore so i had to ask him to stop . afterwards i realised i was bleeding alot and discovered i had a cut on the inside of my vagina . it is very uncomfortable and extremely sore when i need to pee. i was hoping it was gonna go away by now but it is still as sore as ever but not bleeding. what should i do?