Hi, I had unprotected sex on April 29, 2011. The next day, April 30, 2011 I began my period but still took the Plan B morning after pill. Throughout the rest of the month I had unprotected sex and used the pull out method. I am now a week late for my period and have had two negative pregnancy tests. Please help me figure out why my period is late.

The plan B would have protected you for that first time, but unless you took plan B after each time you had sex, that does not protect you.

There is no real "pull out method" there are plenty of spem in the early fluid, so pull out just reduces the chance, but you could easily get pregnant since you had no protection.

But also Plan B will have effects on your period