It sure is an allergic reaction dear. Your dog might have got this allergy because of shampoo. It could be something that he ate. It could be the new carpet or there might be something in grass that he is allergic to. You can give him benadryl. But I would suggest you to take the dog to the Vet first.
Your dog needs to be examined by a veterinarian. Allergies are possible although dogs are not typically allergic to other dogs. Other causes of dermal disease include skin parasites--some types of mites like scabies are contagious, ringworm, contact dermatitis (your dog may have rolled in something), and secondary infections. Stress does not usually cause dermal problems. Stress in dogs often results in colitis or even vomiting. Diagnosing the problem will lead to appropriate treatment. You also need to make sure both dogs are not affected and this is not something contagious.
My dog just got lumps on her body raised and she has vomited clear stuff seems fine she has eaten her food an drinking fine but they look sore and itchy I don't know what it would be plzzz if anybody knows ????
On top of eyes and body