"took next choice 12 hours after intercourse, on day 13 of cycle. i didn&#039;t fully understand how much ovulation increased your chances of conception, so i didn&#039;t know taking next choice was worthless at that time. felt weird the first day, and a little queasy, but really i had no side effects.  i was terrified that i would be in agony and vomiting.  nothing though.  the next two weeks were horrible with anxiety. i started getting period cramps 7 (constant) days before actual period, and would get nauseous in car as well. neither of these two symptoms normally happen to me. it was probably because of stress though.  i got my period today, right when it was due (15 days after taking next choice). ladies, don&#039;t have sex near ovulation if not on birth control. "