post -grooming behavior

Question
My 8mth maltese/Yorkie/Shitzu 7.5 lbs was groomed 3 days ago, but is behaving very unusual. 1st day, totally unmotivated and very quiet and cold as he as he was shaved completely to nothing. I took him to get groomed due to some matts I could not get rid off, but the groomer decided to shave him completely without really asking if that would be okay by me. I asked he get shaved in the tummy area, as those were the tightest knots to me. Anyhow, it's a done deal, but I'm not receptive towards his behavior. He's eating, will go out for walks, but keeps dragging his bum after he takes a few steps/leaps as he's playful,but acting as when I first brought him back from the Vet when he got neutered, as if something down there was bothering him. I asked the groomer if she had tampered with his anal glands, but said she did not think he needed it. He's shivering most of the time, and I got him a thick fleeze jacket that fits him well and covers a good portion of his small torso, but he's still shivers especially before sleep. What's going on?

Answer
What's going on is that you need to brush your dog more regularly and if you do not know how to brush so that mats don't form, you need to ask your groomer to teach you how to maintain his coat between his regular grooming appointments.  Mats don't form overnight, so daily inspection of his coat will help, too.  Usually, and I can attest to this, having been a groomer, the only time a groomer will shave a dog is if the mats are too hard to remove by hand (in other words, if the dog would undergo significant stress or pain), or if the owner requests it.  Sometimes, when a mat needs to be shaved off, it is so close to the skin that the dog is accidentally "clipper burned".  Clipper blades get very hot, and thin hair can tangle in a blade occasionally.  Look for any pink or red areas on his skin.  Sometimes, just as when you get a haircut and the cut hairs irritate your neck, a dog can get irritated by them.  Also, it is possible that your dog does need its anal sacs expressed.  Have your vet do it this time, just to see if there is a problem, since the dog is exhibiting the butt-dragging.  Your groomer probably did your dog a favor, in that hand de-matting is quite painful and stressful depending on the severity of the matting (of course, shaving can be stressful and painful, too, so no surprise if a dog is traumatized by either process).  Hopefully, you can work together with the groomer to get the dog on an appropriate grooming schedule and maintenance program at home, so that this will be unnecessary in the future.  Owners are often well intentioned and kind, yet misinformed about brushing technique, but most good groomers are interested in the dog's welfare and will gladly help you learn.  Meantime, if the dog still shivers with a jacket on, the safe thing to do is visit the vet, just to be sure he didn't coincidentally pick up an infection.