I'm 6 weeks pp, did I start my period?

so since birth 8.26.17 I have been kinda spotting, not much blood at all. (I'm breastfeeding also with formula feeding) anyways. I stopped spotting/bleeding for probably about two days or so, then I woke up one morning and I got bright red/pink blood a lot more than I was experincing. I actually had to change my pad (i was still wearing pads just to be safe and never really had to change my pads) and since then I have been bleeding brown blood and I have been kinda having cramps. I'm not sure if this is still bleeding from giving birth or if my period actually started? how will I know when it'll start?