It is very common and normal for your period to be delayed or different after taking the i-pill (levonorgestrel). Because this emergency contraceptive pill delivers a dose of hormones to prevent pregnancy, it can temporarily affect your natural cycle. Your next period might be a few days early, a week late, or slightly lighter or heavier than usual. However, if your period is delayed by more than a week, or if you feel anxious, taking a simple home pregnancy test can help give you peace of mind.