Got Depo Shot 6th hours of daylight of cycle...Is it still powerful?

I have read that the depo shot is instantly effective after walking out of the doctor's department, as long as you get it in the first 5 days of your cycle, but I got mine on the 6th afternoon at 11:00am. Is it still effective promptly or do I need to hang around until I get my second shot?? MY doctor said to use protection for at lowest two weeks.
Even then, you are single 99% protected. Women have gotten pregnant while on depo.
http://www.rateitall.com/t-330-birth-con...
Check out the reviews of depo provera at the relationship above and google "depo provera lawsuit". Do not get your subsequent shot!
Yes, Depo Provera works immediately. I be on it for 8 years. I am now on IUD because the Depo shot made me gain immensity . With me my period stopped completely when I be on it.