Unexpected bleeding

Feeling confused, hopeful yet worried. 

Today, day 17 of my cycle, I have had some brown discharge and spotting. 

I don't think I have yet ovulated however I have only been doing ovulation stickers for the past 7 days. Could I have ovulated really early ( meaning I didn't do opk's to check) and this bleeding is implantation bleeding? Or could it be bleeding due to imminent ovulation? 

Background: had MC in July at 8 weeks. Periods have been slightly longer since at around 32-35 days.