I had sex with my gf but we use precaution while having sex. And she is not having period of this month. But the thing is when we had a sex last month I gave her unwanted 72 and she had a period in her normal date after that again she had a period for 12 to 13 days but now this month she has a date of his period which is 7th august but today is 7th sep of she doesn't have her period. And she did a pregnancy test 5 days ago and result is negative. So is there any chance of pregnancy? And when she does have her periods of this month?