What Could Recurring Pain Under Left Rib And Blood In Urine Indicate?

Hi. My 18 yr old daughter has intermittent pain under her left rib, blood in her urine for at least 3 wks. The blood is not visible. She has constant nausea, weakness and lost 3 ponds in 3 wks. She was 106 lbs and now 103 lbs. All routine tests are normal. CT Scan w/contrast was normal. Could she have mono? I had it last summer/fall?