My 5.5 months old baby has green poop

Hi all. My 5.5 months LO has been pooping green stools. Went to the PD and doc says might be having diarrhea. But it has been almost a week, but the stools are still green. My baby is on exclusively breastfeeding. He will poop almost right after every feeding. I am very worried. Please enlighten me.

My 5.5 months old baby has green poop