Hi Doctor., My Baby Is 6 Months Old. She Was

Hi Doctor., My baby is 6 months old. she was passing continuous motions immediately after feeding Nan Lolac milk it continued for a week. We then took her to the doctor and he advised us to start using Zerolac and the motions gradually came down. Now she is passing motion once in a day and sometimes she is not passing motion for more than 24 hours. her stomach still remains soft and not bulged. I am not sure whether the milk what we are feeding is just water and coming out as urine. Please let us know if we can wait for more than 24 hours when a baby doesn't pass motion. she has no vomitings and no blood in the stools as well.