My daughter had a UTI when little and that did not happen, however, my son, at 6 years old, kept needing to go. Like you said, right after he had just gone. We even had to turn the car around a few times. The teacher talked to me, because he was asking so much in class. We checked him for diabetes (since my mother, the grandmother, was concerned). We checked everything (I actually brought it up at a sick visit for something else, not that I ran specifically for that). There was nothing wrong. He just went if he felt a little something, and I think, even if he did not feel it (or he had not let everything out before he left the bathroom). He is now 7 (today) and he does not do that anymore. If she is not upset about it, let it go and see if it fades. Maybe also check with the dr. by phone to see if that could have anything to do with the UTI.