Hi, i had unprotected sex on March 10th and that was also the first day of my period. I took next choice on the 13th which was the third day after unprotected sex. I ended my period on the 15th and then started again on the 17th and ended on the 21st. Was that second period caused by the next choice? Also, now i am having cramps , stomach aches, and headaches . is this all still caused by the next choice even though it was taken almost two weeks ago? Also, how long will these side effects last?