Getting pregnant after depo shot

I had one shot of depo back in July of 2013 and I never went back to get any more. I just got my first period since the shot (11months) it wasn't regular at all. It lasted for a week and stopped, it came back 3 days later and stopped. Then a week later I had another period for another 8 days. my boyfriend and I have a very healthy sex life but ever month we get disappointed. So I'm wondering if it's anything to do with the depo shot or if it's something else. Has anyone else had the depo and gotten pregnant after? If so, how long after you stopped depo did you conceive? Is it like the doctors say? It takes anywhere from 6months to a year to even start thinking of having a baby?