irregular period?

is it normal to have a longer gap between your period 4 months after giving birth? i mean i did have unprotected sex once this month, so anything is possible, just curious if it might be normal! i also had a severe UTI all last week and started antibiotics this week, and i've had a lot of stress. i feel like any of these could cause me to be late 😩  just curious if it is completely normal! i see my lady doctor next week so if i haven't started by then i'll definitely ask about it.