My girlfriend was delay until now of her period.we having sex 2nd week of june 2017.but after that she got her monlthly period after we do sex.so i expected that the following month she will have her monthly period but until now she does not having a sign of period i was worried due to before she go to ob after she have a monthly period for her checkup so i was so worried that ob gyne do something wrong to her she so pose to be have a period last month but until now no sign of it can you gave me some advice