Hi there,
I have experienced this a couple of times with my male dwarf hamster. It was hard to tell if the discoloured urine was blood or the result of him eating something (he also has small bits of beetroot in his food).
I started a thread on here a while back, I will try and copy and paste the link.
I did take my little boy to the vets in the end and the vet prescribed him some medication, although they certainly couldn't say for sure if he had a urinary infection or not as he had no other obvious symptoms. However, I did find it made a difference and his urine has been pretty normal ever since.
As she appears very fit and healthy, you could try removing the beetroot from her food for a few days and see if the colour of her urine returns to normal.
Hope this link works!
Blood in urine?