I'm sorry that you and Bindi are going through this
I'd definitely seek out a specialist for sure, and that should've been recommended by your vet after the second or third time this happened. I don't know how must you trust your vet, but if it were me and my furbaby, I'd be looking for a new one
It almost sounds neurological to me, in nature, but of course I'm no expert. I hope that it's something not too serious
