thank u all for your replies.. 醫生asks me to monitor the 便便... coz i'm breastfeeding him & add 1 meal of formula during midnight... 醫生話maybe BB is too small & not used to the formula milk(i used s26)... so i started to 100% breastfeed him last afternoon & today and so far 冇血... will keep monitoring his progress... thank u all again...