can Plan B make your period late if you're on birth control?

Emily
I took Plan B last week because I missed a pill, and I was supposed to get my period yesterday but haven't gotten it. I've read that taking Plan B can delay your period because it restarts your cycle, but is that still true if I'm on the pill? I've been on the same birth control for 4 years and have never been a day late, but I have taken Plan B before and this hasn't happened.