Is this a cheeky scam?

I had listed two items brand new from Ted Baker women’s one still with tags (skirt). Skirt been on a while so I reduced it to 7.99. Trousers 22 pounds. Bargain and I am having a clear out. Had a message would I sell both for 27 and combine postage. Ok as I said want them gone. So I reduced trousers to 20 skirt to 7 and removed shipping from the skirt. She bought the skirt so I’m only getting 4 pounds now for it! I asked are you still buying the trousers. The answer is they are 21.50 not 20. I explained this is the eBay buyer protection fee. No answer 

I have said if this is not to her liking I can cancel the skirt order. No answer. I just feel I’ve been ripped off! Good way of getting an item reduced 😡