Answer to your question 'do dogs have panic attacks', in a word yes! This can also be a seizure type of problem as my dog has. She was diagnosed with 'focal' epilepsy. She
'sees' things that aren't there! She will be lying in her bed, and all of a sudden she is racing away, looking over her shoulder as if something is chasing her. Also she is a 'jerky' type. She will be lying asleep, and sometimes her body just jerks. (I know the difference between jerking motions while trying to go to sleep) Medication has almost stopped the panic attacks. Much better. If you could take a video of this behavior for the vet, I'm sure it would help.