What Causes Vaginal Pain And Itching After Sexual Intercourse?

Hi there, I m writing to you for more information. I had sexual intercourse 2-3 days ago, after over a year of absitinance, I did not use protection as I am now in a relationship with this person. My partner is on the larger side, and at one point he went a bit too fast, in that it caused pain. He stopped when I told him this, and that was that. I felt a little swollen after, but nothing too bad. It has now been around 3 days and my symptoms have changed slightly. I m now very itchy and uncomfortable with a slight burning sensation. It does not hurt to pee but it is uncomfortable to wipe the area, which is my vaginal entrance. I do also shave around this area. It feels slightly bumpy, but nothing too prominant. I m pretty positive that I have not got an STI. Any help would be appreciated.