My 11 year old son has been complaining of body aches, upset stomach, back pain, and pain on both sides in the back.  The upset stomach and back pain has persisted for 3 1/2 days.  The other symptoms appeared two days ago.  He is not running a fever but does complain of hot and cold sensations.
Hi.... Even though there is no fever, I feel that this is still a viral illness due to the nonspecific systemic symptoms. Usually viral infection behaves similarly. If the kid is active and playing around when there is no fever, it is probably viral illness and it doesn't require antibiotics at all. Once viral fever comes it will there for 4-7 days. So do not worry about duration if the kid is active. Regards -