Unfortunately with the breed, they have problems up and down their back. The previous episode could have manifested lower in the lumbar area, where picking her up she would cry. This episode could be in the high lumbar vertebrae, thoracic or cervical vertebrae.
Usually we recommend rest, you can give a baby aspirin with a 1/2 tsp of mylanta and some food because aspirin can be irritating. This will help with any inflammation in the back.
Now if she shows a new sign then we should be addressing that...but I do feel, with the weakness and ataxia, you are dealing with a disc issue.
Dr.Vamvakias
Dr. D.A. Vamvakias
Veterinarian