What are you using to track your ovulation?
They say it's 15 days after your period stops but that's not true for everyone.
a friend of mine went by the 15 days thing and had been trying for 7 months having intercourse every day in the "fertile window". She still hadn't gotten pregnant. She picked up some ovulation tests and started testing every day after her period stopped only to find out that she actually ovulated 3 days after her period. With that now figured out she tried again in her actual fertile window and got pregnant the month after. She is now the mother of a beautiful baby boy.
you may me trying at the wrong time and not even know it. She bought the wondfo brand of ovulation tests of amazon.com because you get 50 of them for like 15 bucks so you'll be able to test everyday leading up to your ovulation without having to spend a ton of money
If you have only been regular for the past 3 months then i think now is the time to try
Just with one depo shot it can take 18 months for your body to become back to normal I got the shot in January and just now started ovulating normal
If it's been over a year, you might want to see the doctor. He or she can run some tests to ensure that everything working correctly and give you some suggestions for increasing your chances of getting pregnant.
Good luck and Keep us posted! :)