pregnant or not?!

So Me and My Boyfriend Been having Unprotected Sex for about a Year now. We've used the Pull-out method . And I haven't gotten pregnant. But Just Suddenly we had sex about 2 weeks ago. I have suddenly Been Feeling Nauseous About Little things. & I've been really tired. I be in class and I can't seem to Keep my eyes open it's so hard. I also Have Suddenly been Really Hungry , I can eat a meal And not feel full, and Usally Before this I used to Eat A big meal And Be full. I don't know what's Up with my body.