I took the morning after pill 2 days after my last period in january. its feb and im a week late. is this normal? taken 3 home pregtests all -ve.

Tests are accurate: Taking a morning-after pill (such as Plan B) can alter the timing of the current menstrual cycle and the upcoming cycle. Menstrual bleeding or spotting should be back to normal, after 3-5 weeks or so. One should check a urine pregnancy 3 weeks after taking the emergency contraception pill, to make sure there is no pregnancy. Home urine pregnancy tests are very accurate by 3 weeks.