I got on birth control last year in November, 2014. I had unprotected sex during December. I had my period for 10 days each during December, Jan. , and Feb. in March I stopped getting my periods. This month I have not seen any period. Although I had lower abdominal pain, nausea, and really sore breasts. I took two urine tests clinically. Negative. I took a blood (quantitive test) negative. I had a pelvic ultrasound to check for cysts. Negative. No baby either. I m not sure what is going on.