Period after stopping birth control

Rebecca • Married to my high school sweetheart. Currently have 2 children Xavier Cole and Mariah Nicole.
So I recently stopped taking the birth control shot because I hated the weight gain. I got the first shot September 28th. My appointment to get it redone (which I didn't) was December the 8th. My dr said that I would or should get my period some time that month. I still have not had one. 
How long did it take for you to have your period back again?