Think continuing to go out with her and spend time in the garden and yard area when its the last time at night is the best reassurance, if she doesn't settle then you do need to think about taking her to the vet.
If she is anything like Ollie making a mess inside is another upset in its self, he is very anxious if he has a mishap or is sick etc. luckily it is very rare.
Do hope she settles, and Min mentioned a plastic bag, my previous cocker Jay would be scared stiff day or night if a flying/moving plastic bags.
Julie