I Had My Last Period On 9 Th Feb And

I had my last period on 9 th Feb and on 15 th I have taken ipill after accidental unprotected sex. Till now ie 27th March I haven't got my period, its close to around 2 months. Previously also I have taken Ipill twice. But my periods were normal those two times.
I had taken pregnecy test twice on 15th March and 24th March it came negative. Taken beta HCG level test on 17 th march, it showed level less than 2 units.
Then my doctorr advised to take Deviry. Is it okay to take. Or I am pregnant. Please help.