Diabetes in toddler?

For the past few days our 2 year old has been having an insane amount of urine. So much so that she will fill a pull up in about an hour. And when I say fill it, I mean it’s sagging almost to her knees and she’s peeing out of it. Her Daycare said that she was going about every half hour and still filling a pull up. She’s been filling her diaper at night and still wetting her bed. I took her to urgent care and they did a urine test and everything was normal but he wanted to treat her for a bladder infection anyways while they send her urine off to culture. He caught me off guard because he said to get her seen right away by her pediatrician to make sure she didn’t have diabetes. She’s had no other symptoms of a UTI but my gut doesn’t think it’s diabetes either. She hasn’t been drinking an insane amount of fluids except today. Her teacher said it was like she could never get enough water. Has anyone else experienced anything similar? The picture of her pull up is for reference on what I mean when I say she fills it, this was only after an hour.