Night feedings

My one month old barely eats at night lately, when she does it's like only 10 minutes maybe then she's back asleep and doesn't seem interested in waking up to continue. Sometimes it's like if I didn't coerce her to wake up and eat she would sleep through the night. When is it ok to not worry about waking baby to eat? And is it ok to let her sleep and not eat even if it is longer than 3-4 hours?