
Hi xenaqueen,
Frustrating though it is for you, believe it or not you've been lucky if this is a first - at 11 months your dog is still very much a juvenile ;) I wouldn't leave my 20 month old youngster for two significant periods in the same day and certainly not when one was for 4 hours - even though she has her mum for company when all the family are out.
She probably is both bored and stressed, particularly as she's had a recent first spell in a kennel environment too. Is it likely you will have to leave her for such lengthy (split) periods again in the near future? Dogs have very little sense of time - you probably notice that she greets you with almost similar excitement when you return from the loo as she does when you've been out shopping :D Mine do anyway (when they've not joined me in the loo in the first place :rolleyes: ).
I'd suggest you try to ensure that if you have to leave her for a max of 4 hours that she's had a physical and mental workout before hand to get her suitably satisfied and sleepy. But then I'd recommend you avoid leaving her for any further time the same day - IMO that's pushing your luck with a youngster ;) Is there a more secure area you can leave her in which is less easily trashed - say the kitchen or utility room if you have one. Make a comfy bed for her, leave her with something carrying your scent like a worn T-shirt and give her a varity of toys including a stuffed kong so she can give her teeth a work out without resorting to damaging your walls, floors, furniture etc.
HTH, regards, Teri