First Time Sex & Missed Period: Understanding Potential Pregnancy Signs

Question
hi i am a 32 year old mother of 3 children my 14 year old had sex for the first time on april the 25 it was time for period to start that same week but it did not on may the 3 she spotted a very light pink on the 4 she did nothing on the 5 spotted light pink on the 6 7 8 and 9 it was brown that was all gave her a pregnancy test and a blood test said she was not pregnant but she is still haveing pregnancy sings could both test be wrong could she be pregnant did i test to early? she did have  her period march the 25 please Email me @ melissaheflin@yahoo.com

Answer
If your daughter has a normal 28 day cycle (from the first day of her period until the first day of her next period) ovulation occurs on cycle day #14. She can only become pregnant if she had unprotected sex on cycle day #13, 14, 15, or 16. If her last period started on March 25, then she would have ovulated on April 7 and could have become pregnant on April 6,7,8, or 9. If she did, indeed, become pregnant on one of those days, a pregnancy test would not show a positive result until 14-21 days later, or between April 21-28. She appears to have gotten her period (although light and spotty) on May 3 and if the pregnancy tests were negative she is not pregnant. The best time to take a pregnancy test is seven days after missing the period. If you have any doubts, take a blood test for pregnancy which is a bit more accurate.