Being it may have been the start of it, she may need an antihistimine injection to get her over the chewing...its a bit of a vicious cycle...she was itching so she started chewing which releases histimines which causes more itching which makes her chew more...you have to break the cycle. An antihistimine will help with that. Your vet can talk to you about giving her one to help.
Let me know if you have any other questions
Good Luck &
Best Fishes