I am sorry your girl did this.
Can you tell me if this was a regular maxi or thiner like panty liner?
What breed is she?
Hopefully she is large enough that this will pass as the other did, however there is always a chance of an intestional blockage.
What you want to do is check the stool for the next 2 days you may actually have to pick through it.Watch for the following symptoms. Vomiting up food or vomiting that last for more then 3 days, no stool production, aneroxia, pain in the abdomen, lethergy.
If you see any of the above signs especially not eating vomiting food or no bowel movement you should have her seen right away.
Adding some metamucil or canned pumpkin to her diet will add fiber and may help her to push this through.
I hope this has helped ease your mind , please reply back if you have additional questions or concerns.