My girlfriend (age 19) started using the pill on June 15th (never was previously on it). The first kind issued to her gave her a some side effects, one being a period for two weeks, so she stopped taking them through 'mid-cycle'. She switched brands and started the new pack on a Sunday. She got her period the week of the sugar pills which would have been the week of Aug 10. She took another pill pack (same kind as month before) and should have received her period the week of Sept 7. Her period has not arrived yet. We had intercourse using the withdrawel method twice during that time period of that pack. She did miss one pill of that pack but took two the next day. She took the pill pretty much within the same hour each day. Her missed pill may have been within a few days of the unprotected intercourse, I don't recall. After missing her expected period, she stopped using the pill. She has taken multiple pregnancy tests since with all result of a negative. The most recent test was on 10/01. Since her stopping birth control, we have used condoms. Despite the negative pregnancy test (prob 4-5), she has had tender breasts and has gained weight. She has been eating a lot more too. She hasn't been truthful with me about certain things which makes for a much greater concern. I don't understand the whole negative pregnancy tests but have some pregnancy symptoms. Her last period was week of 08/10 but negative pregnancy test 10/01. It was not morning urine but she did not urinate atleast four hours before taking the test. She did take a test using morning urine with the same negative result. I don't know when it was taken, but my guess was the week of 09/14.