A.
I took depo for many years, and when I stopped using it I went on the pill for a few months to get my body on more of a cycle. I still ended up using Clomid because even with regular cycles I wasn't ovulating. Use the methods suggested below and/or try ovulation predictor kits. (buy two so you can test for more than 5 days.) It can be helpful to have the temperature charts along with the hormone level confirmation from the tests.
Good luck!