I would go to the emergency vet, now, today, if it was my dog. Put him in the car and go.
It is irresponsible for anyone to advise you differently (over the internet), no vets here.
Even if there was a vet here, they have not examined your dog.
Do not give over counter meds and such unless a vet that has examined the dog and that knows his history instructs you to do so.
PS: The meds he is on may have to be tweaked, changed or discontinued right away, as they may be causing some of the symptoms that you describe.
