Hi Doctor, I M 25, Whenever I Intimate With My

Hi doctor,
I m 25, whenever i intimate with my boyfriend and got a pain in the viginal opening while penitration n its unbearable for me and i have to give up... after 2 days my pain vanishes but this time when i got intimated on the date of my menstruation which was not yet started it again pained alot n i took ipill to avoid unexpected pregnancy within 2 hours of it. But right now m getting a whitish discharge n it pinches me to area whr i feel pain. But sex 1 year back was not at all painful for me it started suddenly. So i want to know 2 things one is tht is there anything to get worried about getting pregenant and second thing is why intimacy is hurting me so much is der anything to be get treated? Thnks in advance doctor