A gastroenterologist specializes on the entire digestive system, including the liver. Since you have this new symptom of
levels along with symptoms of
possible Hepatic Encephalopathy (HE) you need to be under the care of a hepatologist as soon as possible.
However, as Pooh said, keep your appointment with the gastroenterologist so he/she can evaluate your current status and treat you if needed (Lactulose, etc.), and make an appointment with a hepatologist for as soon as possible.