Mama, ito talaga ay kailangan mo na makita ng doctor, okay? Withdrawal method is hindi reliable, at with your period patterns na ganito, kailangan ng professional check-up para malaman mo talaga what's going on, whether delayed lang, hormonal changes pa-adjust pa from postpartum, or something else.
A few of us mums had irregular periods after birth din, especially kung recently lang nag-deliver, pero the only way to know for sure ay blood test or ultrasound talaga. Go na to your OB or closest health center, lalo na if nag-PT ka na before, so they can do proper tests this time. Better safe than sorry, friend.