Testing for UTI?

I think my daughter may have a UTI. She’s been peeing through her diaper the past few nights and is constantly grabbing at the front of her diaper and trying to take it off. She seems uncomfortable when I wipe her too. She’s been running a low grade fever off and on but also has a cold so I’m not sure if that’s related. I’m going to call the doctor tomorrow but I’m just curious if anyone knows how they test for UTIs in toddlers? I keep reading about inserting a catheter but I’m hoping there’s an easier way than that!