What Causes Pain In Lower Abdomen Along With Nausea Post Intercourse?

Hello, me and my girlfriend recently had sex... For our first time, and hours later she started to have lower abdominal pain and from what she says, she is slight nausious. It s been 4 days and she still has it, she also took a morning after pill as well 2 days after we lost it. So the 6th. I ve been researching, we are hoping it s not pregnancy, but it seems kind of early for symptoms. You never know though... Please help.