Can Depo Injection Cause Light Bleeding With Malodorous Discharge?

hie doc, i gave birth 6 months ago, i had my fisrt shot after 10weeks and they called it narex, and had light periods a month after that, when i went for the second one after 2 months i was told that narex isnt good when breastfeeding and they gave me one that i should go back after 3 months. 2months down the line i started cramping and felt like was about to have my periods but very light blood came out the second day i had lots of smelly discharges, am not sure whats causing it, is the the depo shots or the effects of delivering vaginally, hope to get an anser soon.