Could she have gotten dust up her nose?
If she caught something at the vets it will probably take several days for it to appear. Just like a person, it takes a while (usually 10 days) from the time you come in contact with someone else that has a cold before your symptoms appear.
You want to watch for any yellowish discharge from her nose or eyes. Also watch for any coughing.
If she continues to sneeze through the night, you might want to call your vet tomorrow and ask them what they recommend you do.
Sandy, Koke and Lelaska's Mom