I am a 45 year old woman. Beginning on Friday, I began experiencing moderate pain in both knees and in my lower back. That evening I spiked a fever of 101.3 which was gone by morning. The next day, my pain was predominantly in my knees and back, but mo fever. That night, I must have spiked a fever again during my sleep as I woke up with my clothes drenched. Today, I continue to have back and knee pain (aches), but no apparent fever during the day. Any ideas?