It is known as indirect hyperbilirubinemia, which is usually not worrisome, but its cause should be established.
After ruling out hemolytic anemia, it would most likely turn to be Gilbert's Syndrome.
Next Steps
Consult a good physician or
liver specialist.
He may ask you to get LDH, Reticulocyte count, CBC and full
LFT done. Further workup and investigations will depend on that.