Hi, I Have Been Feeling Movement For The Past Three

Hi, I have been feeling movement for the past three weeks or so. My menses started a day early and was really heavy for one day. Not normal for me. I have severe headaches, lower back pain, nausea, fatigue and even fainted. I am also having constant cramping. When I sneeze or cough it hurts. Negative pregnancy test. What could it be. Please help. I dont have insurance so before I go to the ER I want to make sure I am not going crazy.