I have a few questions so I can help you figure out what is going on with your little girl. :)
Can you tell me what food she eats..including any tablescraps?
How many times per day does she eat?
Is she spayed?
Does she urinate or deficate in the house?
Hi Rob...thanks for responding.
The digestive upset (gas) is probably being caused by the tablescraps, so try to limit them as much as possible. Many dogs will regress on thier bathroom habits when a new dog enters the picture, so just be consistant with her and her bathroom breaks.
I would like you to try something, and I think this is where the problem is stemming from. Try splitting up her meals into atleast 2 meals per day of a high quality dog food like Eagle Pack brand food. This is a wonderful, highly digestable diet. You can read about it here:
By splitting up the meals, it will slow her eating down, cause less gas, and the higher quality food will help her maintain better functions in the GI tract. The shivering and panting can be a few different things...pain, stomach upset and hypoglycemia come to mind. By feeding 2 x per day, this should relieve stomach upset and hypoglycemia (low blood sugar)
Good luck and hope she feels better soon :)