Kasianni, Silk had hardly a crystal in her urine either but had huge stones, see below.One more was sent away for analysis. The vet didn't find them by palpation. An x ray would be a way to eliminate the possibility of stones. ( By the way, I tend to tell the vet when I want x rays. LOL. They probably think I'm a bit of a pain. ) Are you still seeing blood in her urine?
Barkingdog, sorry about your loss
and of course talk about your dog, I think Aide dogs are very special, you must have had a strong bond with it. So sad!