I took an ipill on 18th dec which was 6th day of my periods. I had withdrawal bleeding in 28th December. I was supposed to had my periods on 13th Jan but haven't got yet. U took urine test 5 times, the latest one in yesterday but every time it's negative. I always had my periods on time and this was the first time I took ipill within 4 hours of sex. M quite tensed, is there any chance of pregnancy, by when can I expect my periods.