I Stopped Having The Depo Injection At The End Of

i stopped having the depo injection at the end of march i had what thought was a period about 5 or 6 weeks last lasting about 5 days of mostly brown blood some days were heavy and red though, i then stopped for a week and a bit and it came back as more spotting on and off for a couple of days, nothing since then. i am trying to concieve my second baby how do i know if this is normal and if i am ovulating?