Normal lang po ba ang delayed or irregular periods during breastfeeding?

Hello po , may tanong lang po sana ako. First time mom po hehe. Normal lang po ba ang irregular or late menstruation after birth and during breastfeeding ? September po ako nanganak, at bumalik po ang 1st monthly menstruation ko last month December pero ngayong month of January delayed na po ako ng 4 days . Normal lang po ba ito mga momsh? Thanks po sa sasagot. 🥰