Birth Control

I had my son in July of 2016 a few months after that I got the depo birth control shot. I didn't like it. I was supposed to get another one in December but decided I didn't want too. But, now I still have not had a regular period. I have had some spotting occasionally. Has anyone else had problems with this certain birth control. We really wanna try for another baby but not sure what my bodies doing since the birth control.