my lab also has a sore pad,it is not cut,looks more like a childblain,red and sore she is in occassional discomfort about the size of a sixpence,should i try newskin.
Newskin is specifically for cuts/grazes and sealing them from dirt etc. In your dog's case it could be a foreign body has worked it's way under the skin, so better to have it checked by your vet IMO.