Not pooping

My baby is 12 days old. 1st week nia aycnormal pooping every dede. Pero nung 10th day nia, naging 2x a day sya magpoop pero sobrang dami. Regular din namam ang burp at utot nia. Pero yesterday hindi sya nagpoop the whole day. What should i do mga mommies? FTM here. Plss help