Should I Not Give ORS To A New Born When They Have Green Stool And Frequent Bowel Movement?

Hi my 1.5 month baby is having frequent motions and green stool from two days . pediatrician prescribed.she got 6 week vaccination day before she started green stool. Pediatrician prescribed bifilac twice in breast milk and ors to her ,but it s written it s not safe for small babies .what should I do ? Should I stop giving her ?also last night she cried alot for almost 5 hrs .