It can take 4-10 months for the depo to wear off. Here's a link. Hope it helps.http://www.conceiveeasy.com/get-pregnant/getting-pregnant-after-depo-provera/
We tried for 1 1/2yrs before finally getting pregnant. Not getting ur period is not a good way to go about if u are prego or not. I skipped a lot of periods and i remember the first time i got my hopes so high i cried for a week. The next like five times same thing....then i lost all hope. We went to the dr after one year and we wete directed towards fertility treatments and my heart dropped. I thought 'im done for. Ill never be able to give a baby for my husband' before we started the treatment we found out we were pregnant.
I would go to ur dr and start talkimg about fertility treatment. Do sperm motility and wuantity and quality test. Do ovulation test. Just do any tests you can and talk about if u should have sex every day. Or every 48h, it differs with the sperm motility and ovulation when the best chances r for u to get pregnant. Good luck!