Good luck with this one. Depo shot can stay in your system for up to a year. So you may not start a period until then. All bodies are different and depends on how well your body reacts to certain medications. Depo is a really bad choice of birth control and I do not reconmend it to anybody.
It can take upto 3mths, i had the implanon and didnt get my period for 3mths after it was taken out, my sister was 4mths after she stopped her deprovera shots