TTC after Depo

So I got one depo provera shot back in March but didn't get my second in June because my husband and I decided to start trying. I haven't had a period since March but I cramp a lot like I'm going to start but nothing. I took a pregnancy test the other day because I've been feeling sick and got a faint positive but since then have gotten negatives. Anyway, anyone have any advice about ttc after the shot? I know it takes some women a long time and honestly I'm already feeling discouraged.