I ve been regular for over 10 years, give or take a few days. I use calendar planning as my method of choice and condoms. I had unprotected sex. Kinda cut it close to my ovulation window. My period is 5 days late. First pregnancy test was negative (Sunday), second was negative (Tuesday), third was positive (this morning). I went to planned parenthood and they did two tests. Both came out negative. They gave me Plan B. I took it around 1:30pm. Right now, I have nausea, weakness and shakiness... I ve never had these side effect from Plan B. Could it be possible I m pregnant?