Hi, Am an south Indian married woman with 24 years old. I took duphaston twice a day in ten days for the past two months. On the first month period occurs after two days, the withdrawal of duphaston. But this month,no period comes after 9 days. I feel menstrual pain sometimes before 3 days, now headache too. I ve done home pregnancy test thrice,but its negative.Is there any chance for pregnancy?