Yes take her to the vet... Nowadays with so much going on anything could be wrong with her.. An allergy or bacteria...
Try 1/2 tablet of equate brand benedryl. That will stop the itching. Take her to the vet to make sure that it's nothing more than a "hot spot " .
It could be anything from an allergy, anxiety, flees, etc. The some hidrocortisome spray solution or cream over the counter to help with, there's also shampoo specifically for itching. All that might help, but the best option is take her to a Vet. SPCA and Animal Humane Society both has affordable price. One last thing, make sure the while scratching doesn't cut her skin. Hope this help. Good luck!
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