Blood on diaper

Hi all, I need help ! Ftm here and my newborn is just 16 days old. The first week her poop was watery and needed to change every feed. Few days back her poop became dryer and the number of poop reduces to 3 times a day. We discover blood on her diapers and was worried if she is constipated. Currently we are feeding her nan supreme pro HA, if she's having a constipation, any other fomula to recommend?