Good Morning
(or whatever time it is there). I think she is just a very playful Yorkie or one with an itchy head. It doesn't sound like shunt to me at all because she isn't pressing her head. Yes, Yorkie who itch COULD have liver problems, but if that is the only symptom, I wouldn't be concerned at all. If she is that itchy I would look to allergies but it sounds like she is just playing. I would never ever tell a Yorkie owner not to test for a liver shunt because they are so common in the breed though. By the way, you wouldn't really be putting her through much. It is just two blood tests.