[Ringo1]

I'm sure that this is very disturbing behavior after following your routine all of these years.

If her health checked out ok; could this be the beginning of doggy dementia? My Maltese started around age 11 - pacing. But he was not shivering and whining; just started out continually pacing of an evening and eventually during the day.

I hope your Vet can get to the bottom of this - everyone needs their rest.