Hi don't worry period s may delayed due to stress or other cause . & if her period s are regular then you had intercourse in safe time .

Hello... Well dear since you are telling that she has missed the period and pregnancy is also negative it's quite possible that the reason is something else.. please meet a gynecologist once.getit examined and then you can start in treatment like deviry 10 mg one a day..hope you understand....so once get it examined.... thank you....