Does your dog have any bald spots?
How much does she weigh?
This definitely sounds like canine atopy, or allergies. This can be due to environmental allergens, insects or foods. It is hard to tell which exactly is causing the problem without testing so many people treat the allergy symptoms of their pets with antihistamines or steroids since allergy testing usually runs around $300.00. The reddened, itchy, flaky skin and foot licking/chewing are all signs of canine atopy. You can try treating with Benadryl, 1 teaspoon or 1/2 tablet, three times daily. If this doesn't work then you may need to see your vet for some prescription steroids. You can also use a hydrocortisone spray on the red areas just to help reduce the itch and inflammation.
Please let me know if you have more questions,