Make an appointment with a veterinary internal medicine specialist for diagnostic testing and treatment options. You implied the regular vet has not been helpful.
That’s the only solution I can think of. Ask your vet for a referral.
Best of luck
Ps: You can always go to the emergency place, they diagnose 24/7.
I would refrain from giving the dog over the counter meds and such unless recommended by a vet that has examined the dog.
Show the video to a veterinarian that examines the dog, as soon as possible..
I did not view the video.
