painful peeing

most of the time, my body physically wont let my boyfriend inside of me, no matter how wet or turned on i am. he said it’s like my body is putting up a wall. once we force it in though, it feels fine. but afterwards, i have excruciating pain when i pee for a few times after sex. it’s usually better by the next day or so, but my vagina is always in so much pain that i have to wait a few days to have sex with him again. i’ve mentioned this to my doctor but i don’t think she listened to me. i’ve had several partners and NEVER had this issue before. i’ve been tested for STDs multiple times and they always come back negative. why does it hurt so bad, and why does peeing hurt worse?