If this is the same puppy you mentioned in another thread, and she is only 2 months old, she is too young for trips to a dog groomer. She hasn't yet developed enough immunity to be spending time around other dogs, or in places where other dogs are kept--she is still too susceptible to contracting canine diseases before she has completed all of her puppy shots. And young poodle puppies still have a very fine silky puppy coat that should not be shaved down. Having a long coat is normal for a puppy that age, and the dog will not feel warmer if her coat is left long--dogs do not perspire through their skin, they cool their bodies down by panting. Just make sure your puppy has lots of fresh water to drink if the weather is warm and don't let her get over-heated, she is still a very young puppy.
You obviously seem to want to take good care of your puppy, but I'm not sure you know how to do that. I suggest you get a good book on puppy care that will guide you and help you to better understand the stages of a puppy's life and how you can best care for them at each stage. And I'd also suggest that you get a book about poodles so you understand their rather unique grooming needs and how you can best take care of those needs, and so you can learn how and when poodle puppies should be groomed and how you can care for their coat on a daily basis, what types of brushes you should use, how often to brush them, etc.
You should take the puppy to the Vet if she is not acting normally. It is not normal for a puppy to stop eating or drinking. Puppies do not worry about their "image" or how they look, but the dog may feel physically uncomfortable, or she may be ill, or the experience at the groomer may have been very frightening for her. You need to take her to see the Vet. And you do need to read and learn about proper poodle puppy care.