Daughter is sick and DR can't figure out the problem?

On Tuesday my 16 yr old daughter woke up with her forehead swollen quite badly on the left hand side. As the day went on the swelling moved to her mid- forehead and was causing tremendous pressure on her head and eyes. We went to the DR and he took some blood tests,a urinalysis, and a CT scan with dye contrast and didn't see any problems with her sinuses, no infections etc. The next morning the swelling was down in her eyes almost swelling them shut, we went back to the DR who again ran more tests finding nothing but decided to try to treat it like an allergy with prednisone which got rid of the swelling. Last night my daughter was isnexcruciating pain all over her arms,chest,back of her neck ,ribs from just a touch or the pressure of laying down. More tests in the ER, the only thing they could find is that her white count is elevated and still they don't have a diagnosis. I am hoping a DR will read this and know what is going on. If so please give me a guess on a diagnosis.