cody the red nosed rat bag

cody has a bloody nose , he has been to the vets and he cheacked him over n sed it wasnt repspatory (sorry cant spell) and gave him antibiotics as he had a tempture, we then took him for a check up and we were told he was fine, can rats get nose bleeds? its not a reprotory problem as he has no other symptoms and our vet is great but i was so worryed about cody hes bin bk 3 or 4 times and each time hes just said hes only got a tempreture apart from the last 2 times when he sed he was fine im a very nervous person and dont do well in confrontation so i dont like to ask questions face 2 face. so i didnt ask what it could be, back to the point can rats get nose bleeds as the blood isnt always there! please help thanks