I Just Gave Birth To A BabyGirl On March 15, 2012... 3 weeks later on April 5, 2012 I got my first depo shot... 1 week after depo on April 13, 2012 had sex while on my period... I know I wasn't soppost to have sex because I gave Birth, but I did... Is there a chance of me being pregnant?

It would be very unlikely as Depo Provera is one form of birth control that works from the start. See what happens when you would expect your next period.