Sorry to hear about your little Yorkies sore feet. I think that the vet may suggest an antibiotic to prevent infection.... I would make an appointment just to make sure. (and for peace of mind.... It would be bad to an infection there!
) Hope everything heals quickly!
We use Excel Paw Wax on Shelby & Seymour when we camp. (and sometimes here at home, too) It is a wax that you apply to the pads of their feet and it protects them. You can get it at Petsmart (online, also).
Here is a description of Excel Paw Wax:/Protects and conditions dog's paws all year round. Helps prevent paw damage from gravel, asphalt, ice, snow, salt-treated roads, hot pavement, and all hard surfaces. Also provides grip on slippery surfaces. Ingredients: White oil, paraffin wax, rosin, silicon dioxide, perfume.