You did several times unprotected sex including ovulation time and took postinor 2
pill within 72 hrs.
Postinor 2 pill has effectiveness 90-99% depends on taking time after intercourse.
So wait for the next coming period and do home pregnancy
test with urine/blood for hcg after 1 wk of missed period. You may get withdrawal bleeding within 7 days due to effect of pill and other side effect like earlier/delayed period,nausea
Practice safe sex in future with using safe period/OCP/Condom etc. Be well.