Help pls

Victoria

I was put on depo back in January of 2015 and had my last shot April 19, 2018 I got my period back in July 2018 but my periods were abnormal I had two every month for 4-8 days. So far I’ve had regular periods since October(once a month for a full week not too heavy not too light) I’m just wondering when my fertility is going to come back ):