My fiance is on birth control and takes it regularly. Last month she got her period on time but only bled 1 day and it stopped and i guess she didnt bleed that much either. now this month she was 1 day late but didnt get her period, she is spotting. we're careful when we have sex and i very rarely ever ejaculate inside of her. Is this a sign she is pregnant or what could be causing this to happen?