almost 9 months postpartum. DELAYED.

hello mga mommies. I just want to ask if meron bang same case sa'kin. last March 30, I had my first period after giving birth almost 8 months na nun si baby. then I was expecting to have my period on the last days of april pero wala. 1st week of May I've got this redish brown discharge akala ko start n ng period ko. pero hindi sya nag tuloy tuloy. nag pt ako last May 3 negative naman. kagabi meron parin akong pinkish-brown discharge pero wala paring period. ano kaya yun? is dis hormonal imbalance? am I pregnant? btw pure breastfeeding po ako. thanks