Depo Birth Control Shot/Pregnancy Test..

Theresa • I am 29, I have been with my husband for almost 12 years and have been married for over 7 years! 8/15/14. Finally after trying for 4 years we had a precious baby boy! And on the first try we have our sweet baby girl. 🥰💚💚
I have not had my period for six months because I was on the Depo birth control shot. I know it says it takes 3-6 months to clear from your system but I do not believe that because I know two people who got pregnant not even a month after they discontinued the shot. Since I have not had my period yet does it mean there is a possibility I can get pregnant? It happen to the two people I know. Also, how soon can I take a pregnancy test