Bring her in and away from the dog (obviously). Do you have any antibiotics? If so, what do you have? It is really good that she is eating and drinking.
Welcome under not so good circumstances. There are many duck people here that can help. @Debbie292d has given you the link to your State thread. Here is the link to the duck forum: https://www.backyardchickens.com/forums/ducks.42/. You may want to add good quality hawk netting to their run area