Caring for a Three Legged Dog or Cat

Hello all - It's been a long time, though all of you here are never far from my mind. 

My husband and I just returned home from a week in Hawaii (woohoo!) but after we brought the dogs home from their "hotel" we noticed that Barret was hopping around kind of funny. I thought that he had maybe had pulled a muscle or something, which he does from time to time because he's an absolute nutball, and it would resolve in a day or two. 

Well a day or two has passed and he is still limping. We've determined that we think it's his remaining front paw that is giving him trouble. He avoids putting weight on the front of his foot.  He still lets me touch it and wiggle the toes, though he never liked his feet touched to begin with. I can't see any cuts or splinters, or anything physically wrong with his paw. It is a little bit warmer than his back paws to the touch, but not red. Nothing seems wrong on the rest of the leg and he still gets around, just a little more gimpy than usual. He shows no other signs of illness or pain - still eating, playing, etc. 

So I am asking this great hive-mind for advice. I don't want to overreact and rush to the vet (my regular vet is out this week, but I could see another if I needed to)... but on the other hand he is my baby boy and he's already used up his spare leg! I mean... what could it possibly be, and what would they do for it?

Anything I can do to speed recovery (other than keeping him off the paw as much as possible... which is easier said than done)?

Ah, the joys of parenthood , am I right?