ok i hope im not too late to talk to you about this. yes, anytime you notice a groomer is frazzled like that, kindly ask her if it would help HER out if you brought the dog tmrw. she will probably kiss the ground you walk on for making her day a little easier. that said, there is no excuse for any wrong behavior from a groomer just b/c they are having a bad day. however there is really no way for you to know what happened. i will say this about vets, i have known many groomers (myself and coworkers) who have done nothing to a dog, yet had the customer call and say the vet said they had to have been injured at the groomers. im not saying he is lieing, im just saying dont go by his story completely. ive known people to say "we took him to the groomers and now hes like this" so vets autometically say, oh he fell of a table or was hit. your dog probably wasnt very good for the groomer that day, what with her being stressed out, she probably carried that on to all the dogs, who all in turn fed off of each other. you get one dog in a grooming salon that is stressed, and pretty soon all of them are giving you a hard time (which makes you even more frustrated). just reading the story, the most logical explanation is he freaked out with the muzzle on and could have hit his head on the grooming arm, or thrashed and hit his head on the table. something obviously happened, and instead of the groomer telling you anything that could have caused it she is upset with you. this alone would tell me something about her. anytime someone has called me and said something was wrong after grooming, i go over the entire groom in my head and tell them anything that could have caused it. he could have jumped off the table wrong. he could have hit himself in the kennel.
in the meantime, you do need to keep up with the grooming so he is not traumatized. but i would take him somewhere else. whether your groomer did something to your dog, she didnt handle the situation well at all. explain the situation to the new groomer. tell her what happened without pointing fingers, and just explain that the dog is scared now and needs to be reassured through the whole process. dont do too much on the first groom, just a bath and tell her to do whatever trimming she wants based on what the dog is ready for. if you avoid the situation, the dog could develop a huge problem with grooming, but if you find someone nice and calml, im sure the problem can be avoided. i have had many people come to me in a similar situations and as long as you reward the dog for any good behavior and kindly redirect any bad behavior, the dog will turn out ok, especially if you say the dog was so good before. | 
Horrible experience at the groomers - HELP! 
Groomer 
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