What Causes Fatigue, Nausea, Pain In Abdomen And Vagina After Sex?

I had sex for the first time last week and it was protected. After that I am feeling sick and tired. I always feel like throwing up. I m always tired and I have abdominal pains,pain in vagina and back pains as well. I also have some kind of black stuff on my panty. Does that mean I m pregnant?