Oh Pippin! You will feel better soon.

No personal experience, but bichons are prone to stones and several have had to have surgery. Do be sure to stick with the special diet after the fact. My friend has Mattie, who had the surgery. Well, the special diet was made by Science Diet, not the best company or food. So she decided to research and control things on her own. 5 months latter, poor Mattie had to have the surgery AGAIN! Now, my friend keeps strictly to the vet prescribed diet. She takes in a urine sample once a month so any crystals can be found BEFORE they develop into stones. She did ask the doc to use the Royal Canin prescription food rather than the Science Diet, but he explained why Mattie couldn't use that one. Whew what a time that was!