Deviry related. Can i start the course?

Can i take deviry at any given point of time in the cycle? I had unprotected sexual intercourse on 8th and 9th march i took ipill twice on 8th march itself and on 9th march late night. Both were before 24 hours. Though there was no ejaculation i was worried of the precum. My last month period date was 22nd February. I suffer from PCOD so i don't have a fixed cycle. Past 2 cycles of mine were 38 days. Today that is a week after taking the ipills all of a sudden i had severe pelvic pain. So i went to pass stool and it reduced immediately and then i took a pain killer. I want to know when can i start taking deviry and for how many days to get the bleeding and know that I'm not pregnant. It is way to earlu i guess for me to take a pregnancy test. Please explain when can i start the course? Really tensed please help