I Had Sex With My Bf And My Only Protection

I had sex with my bf and my only protection was postinor 2 right after the intercourse.i took 2 tablets right away.according to my period calendar app,I was fertile during the time I had intercourse and it's a day after my ovulation.we got intimate again the following morning and he ejaculated inside but we depended only on the postinor2 that was taken during the night.since I stopped using oral contraceptive 8 months ago,my cycle has been unpredictable,it varies between 30-35 days and my previous cycle was 40days gap.im having very light bleeding 6 days after taking postinor2.what are the chances that I might get pregnant?im worried due to the abnormal cycle that I experienced the past 8 months.is postinor2 enough to prevent pregnancy?