If the total bilirubin is high then you must get the direct (conjugated) and indirect (unconjugated) bilirubin done to see which component is high. A slightly higher than normal indirect or uncongugated bilirubin may be seen in increased breakdown of red blood cell as seen in sickle cell anemia, hemolytic anemia, or due to certain drugs (such as anti TB drug rifampicin), impaired conjugation of bilirubin as seen in Crigler-Najjar syndrome type I and type II, Gilbert syndrome (however in these two symdromes the value of indirect bilirubin is pretty high). Similar picture is also seen in sepsis, vitamin B12 deficiency, hypoglycemia and hypothyroidism.
Increased direct bilirubin is seen in bile duct obstruction (due to stone or tumor), cirrhosis, hepatitis, intrahepatic cholestasis (bile builds up in the liver due to obstruction, genetic causes, malignancy, metabolic disorders etc) and Dubin-Johnson syndrome (very rare).
Also other liver and pancreatic enzymes, ESR, C-reactive protein, albumin and total protein, and prothrombin time are the other tests which should be done. If any of these are high, then a CT scan would be more diagnostic than an ultrasound.
Please consult a hepatologist/liver specialist. Take care!
The medical advice given should not be considered a substitute for medical care provided by a doctor who can examine you. The advice may not be completely correct for you as the doctor cannot examine you and does not know your complete medical history. Hence this reply to your post should only be considered as a guiding line and you must consult your doctor at the earliest for your medical problem.