nervous & trembling

by marvel
(Maine)

Our mini schnauzer is 9 years old. She has always been afraid of loud noises and storms. Lately, she is nervous and trembles most of the time. She is on thyroid medication. She keeps her tail stub tucked in and paces around, or hides underneath furniture. It used to happen now and then, but for about 2 months, it is pretty much the norm for her now. So nervous. Why and what can i do for her?

NOTE FROM LINDA AND MAX:
It sounds like something had changed to make her constantly apprehensive. We have heard of other Schnauzers experiencing this intermittently and would be extremely interested to know if you get to the bottom of it.
The fact that she is constantly doing it is worrying, although it does seem quite likely that it could be behavioural, something has triggered her fear/apprehension - or is it a cry for your attention?
I think I would forget the expense and take her to the vet. It may be that a dose of tranquilisers will restore her to her former self.
Good luck.