My son had the same symptoms and he has finally been diagnosed with Lyme Disease. He never got the bullseye from the bite, but he was exposed to laboratory blood. He didn't feel much better with oral antibiotics, but when they began the IV antibiotics he was fine. Get her checked for Diseases. If you live in an area where she could have been bitten by a tick....there you have it. Good Luck! Also, think about Fibromyalgia...it's very painful as well.