Blood panel completely normal except bilirubin

Just got out of the ER. My bilirubin came out slightly elevated. Its 2.1. It was 1.7 in August. Today the doctor said all the liver enzymes are within normal range except bilirubin and hence she can’t really tell what’s really going on. She asked me to consult with my GI doctor. Anyone had this kind of experience with bilirubin?