Need help diagnosing a problem with my dog.?

Question

Before anyone starts screaming at us, I plan to take her to the vet tomorrow, but would like some help in pre diagnosing her problems. Anyone with vet exprience can really help.
These are the problems my dog ( a sheltie ) is expriencing.
naseau
vomiting - though only liquid and not a lot
lathargic - but she is moving around just asks really sick and tired
drinking a little but not as much
eating normally but this is a dog who would steal your burger as you walk past and she has no real interest in doing that now.
She is walking with her head hung low. I found that odd, but my hubby says it's nothing.
Breathing normally
Going pee and poop normal

Any help is prediagnosing is appreciated. I'm hoping she just has a tummy ache. It's been about 24 hours since she started acting this way and I'm concerned but just can't afford the high emergency room costs so I have to wait till the vet opens in the morning.
I should also add this is a dog that stays in doors.

Answer 1

Sounds like she may have eaten something that made her sick- did she find chocalate somewhere or did someone give her some- these sound like the signs of chocolate poisnioning, but hopefully she will make it til you get to the vet. I have a book that lists all household poisons and the symptoms for dogs I will keep looking and if I find something I will edit my answer ok!?