I have had a reoccurring mid grade fever of about 102F for the last couple of days. It appears along with a face rash. I have been having a reoccurring fever of 101F for one day every week for one day. The fever breaks by morning. The first week began with extreme fatigue. The accompanying symptoms are: severe nausea, lack of appetite, chills, body aches, stabbing joint pain in the hands, feet and knees, tightness in chest when lying down, difficulty breathing, nasal congestion, sinus pressure headaches. I have seen a doctor about this, she tested me for flu, and when that came back negative, she diagnosed me with upper respiratory infection and prescribed Cephalexin. After taking the first two pills the fever and rash returned as well as the fever. I continued taking it assuming it was my body fighting the infection, however, after the fever broke this morning, it returned again at noon. Should I stay with this prescription or seek a second opinion.