Dog constantly scratching and digging??

I have a rat terrier/yorkie mix. I had him groomed several weeks ago. Where I take him they give him two baths, cut his hair, clip nails, etc. He was around other animals also. My question is. Since then I have really noticed him scratching alot. I have tried an oatmeal bath. When I look at the area it has little sores and seems to be getting worse. My other dog got the same treatment minus the hair cut and she has no reaction. I looked up Manges and this is not what it looks like. Any suggestions as to what it is or what to do to help relive his itching?? Thanks for any suggestions.

hi there!
it could be fleas or dry skin. just in case, i would take him to your vet. they can tell you exactly what it is, then you can treat him accordingly. an itchy pup is an unhappy pup. good luck!! I have a RT and i love her too much. she had the "red mange" when she was a pup. ugh! but i treated her according to vet's suggestion, and now she is perfectly happy, well, and i love her so much. her name is maggie!!