[cchu]

I would def take him to the vet before you give him any medication. It does not sound like Duke is in too much pain but do realize that he is in pain. A dog would not limp if he wasn't. The leg is obviously bothering him since he does not want to use it.

The symptoms you described is very similar to Zoe's when he was diagnosed with luxating patella. This may not be the case for you but whatever it is, get it checked out and update us so we can all root for Duke to get better!