Just curious

Danielle
Been off depo 1 year free now, spotted some what a few months ago last 2 months been reg, every 28 or so days... However I'm abit confused if you would class brown AF as actual af, I know this may sound really dumb.. But can you actually class it as a period regardless of colour? 
Lasting about 4 days, medium flow x
Is this a good sign? 
I just read that brown blood is old blood which is understandable I was on depo for 6 years.. But would u say that I'm ovulating if this is happening?