What does bleeding after taking ipill indicate?

Patient: Hi, my period date is 6th and on 18th night at 1’o’ clock I had unprotected sex with my partner, I took ipill on 20th at 8’o’ clock before 72 hrs. After 6 days of taking ipill bleeding started, is it withdrawal bleeding, am I safe now. Please answer me doctor

Symptoms: Bleeding after 1 week of taking ipill