Hi, We Had Unprotected Sex 8 Days After My First

Hi,

We had unprotected sex 8 days after my first day of periods n took postinor 2 16h later. After 5 days I experienced bleeding which lasted for 2 days. We had protected sex 2 times since (used condoms) but i haven't gotten my regular periods yet. It's a week late. What is the reason? was the bleeding in between considered my normal periods? Please help