He could have logged something in it, he could of gotten stung by a bee , possibly a tick, or a bad sore. For treating something logged either get him/her when just waking up or while sleeping get a good look, if something is logged get tweseirs and pull. Or take it to the vet to get it looked at, if its the bee do the same thing and if its a tick get tick remover or what we did, but my scare him/her is try freeze away wart remover cause we tried it and it worked. But since its a tiny dog just get tick spray. Hope this helps and sorry from my spelling error! Good luck!
My Little Yorkshire Terrier Has A Big Red Boil On The Outside Of His Paw (its Not In-between The Toes). He Has Been Licking It For A Few Days And He Wont Let Us Touch It. Oh And It Does Have Pus Coming Out Of It, What Could It Be? How Do I Treat It?
Our rat terriers have the same problem, bone spurs, the only thing a vet will do is give them a shot of anti-biotics. Normally they come and go, but if it becomes severe enough, the vet can lance and remove it.-- Have you any thorn trees or sand spurs in your yard? These can cause problems too.
Try using a warm washcloth and put it on it if he will let you other wise he may need to go to the vet and get them to treat it