My 9yo son has an unexplained high fever, nose bleed, stomach ache, burning on urinating but ua was normal at ped office yesterday. eating/drinking ok?

What else?: This may be serious. A negative ua doesn't explain the other findings, your son needs a full evaluation. What did the pediatrician tell you? What other tests are pending or will be done? What did his physical examination show? Talk to your doctor about all this.

Other symptoms...: How many days has he had the fever and how high? Any respiratory symptoms (cough, runny nose or congestion)? How long was the nose bleed for and has he had any more? If he continues with the fevers and/or has nose bleeds that are heavy (>20 minutes), i would bring him in to have a CBC (looks at platelets, white and red blood cells). I hope he feels better soon.