What are you doing here?
When people get to a certain age, they become set in their ways; they like things to be done a certain way and they have a hard time with changes. In a similar way, dogs are set in their ways; when they’re used to see their vet in the clinic or their hairdresser in the salon, seeing them anywhere else might be confusing for them.
The expression on this dog’s face is a mixture of shock and panic, and we can’t find a better explanation for this expression that the one suggested in the Snapchat caption. What could possibly startle her this way, other than seeing her hairdresser outside the grooming salon? She’s always thought her vet couldn’t exit outside their clinic, and the hairdresser couldn’t exist outside the salon.