Is Depo Injection Effective With An Eight Day Delay?

Hi, my name is Kimberlee. I've started taking the depo provera shot in September 2010. I got my third short April 7th, 2011 but, it was supposed to be March 16th. The only reason it changed was because of insurance issues. Am I still covered by the depo shot after being only one week and a day late for it?