Angel,
Definitely insist on seeing, at minimum, a GI doc. A hepatologist would be best. Ask to have her autoimmune markers checked for Autoimmune Hepatitis (AIH), Primary Biliary Cirrhosis (PBC) and Primary Sclerosing Cholangitis (PSC). They usually start with ANA (anti-nuclear antibody) for an initial screen for any autoimmune disease. Then they have specifics for the liver/gallbladder related ones such as ASMA, AMA, anti-LKM1...for starters.
If the only thing they tested for is Hep A, B or C, you may only get negative results so be sure to ask for more blood work. If they think it may be her gall bladder backing up, you can request a HIDA scan to monitor the flow through the gallbladder.
And just to clarify...the word 'hepatitis' only means inflammation of the liver so it may not be any of the above but it is critical to determine what is causing the inflammation. Carol's question re: tylenol/acetaminophen is a good one.
Keep us posted!