Cassie (female, almost 8, on soloxin for thyroid) was on a walk all the sudden she holds her right front paw up and cant seen to put any weight on it she just collapses it. I check pad and nothing there... rotate leg with no issues... Put foot down try to get her to walk she takes a few steps still collapsing leg then she starts the same thing with her back right leg. I get in her face and its like her eyes are just fixed. Then she starts circling to the right 3 or 4 times. I hold her still for a few min and start walking her forward now she is walking on all legs but keeps listing to the right. She did this once about 8 months ago but we were at home. This and the one 8 mo ago lasted about 4 min then all is well. Any Ideas?