Had the flu went to the Dr after peeing dark orange. Urine test showed that there was a small trace amount of blood. Concerned about the cause of blood?

May be okay, but... This or similar question has been answered many times. Seeing trace blood on chemstrip testing of urine could be okay, but it is advisable to be further tested with microscopic exam. If UA shows >5 RBC/HPF, that is significant and needs further evaluation. How? Go to blood in urine on http://formefirst.com/onDealSickness.html. But, it is still a better idea to be checked.