birth control!

I need some help please. I am currently in the process of trying to have another baby. I have a 5 year old son and after I had him I began the depo shot for 5 years. I have been off the depo shot for two years in May. Is there anything I can take to help my chances of becoming a mommy for the second time? Anyone know how long it takes to get out of your system? Or any suggestions on what to do.