Weird poop last 3 days

Ka

My son is formula fed. He’s been on nutramigen for a month. His poop has been normal poops, but the past 3-4 days he’s been pooping like this but a darker green. This poop was his poop like 10 minutes ago and this morning it was super runny and dark green. Is it diarrhea? He has a Doctors appointment on Thursday for his shots. Should I wait it out or call tomorrow?