Advice on when to TTC

Abby R. • Wife, Mom to Mickey and Phoebe 💙💜
I got the Depo shot back in May just for the sake of trying something different to not take pills. My appointment for the next shot will be the 2nd week in August (which I am not going to get). I know that it takes a little longer to get back on track- but I have been bleeding/ spotting for about 3 weeks now. I'm wondering if this is normal or anyone has experienced this?
How soon have any of you been able to get pregnant after getting the Depo shot? 
My periods are very irregular anyway so should I just constantly take ovulation tests???