I took plan b on june 2, three hours after intercourse and my period was due june 25. i am now late 19 days. is that normal?

Pregnancy Test: Plan B is only 50% effective at preventing pregnancy. While it is well known that Plan B can change your menstrual cycle, you must first do a pregnancy test to see if you are indeed pregnant or not.

It may be BUT: Plan B works by hormonally interfering with fertilization of an egg. It is also possible that this type of emergency birth control prevents implantation of a fertilized egg in the uterus by altering its lining, and periods can become irregular, especially after its use. However, check a pregnancy test too. Best wishes.