There are many causes of hepatomegaly (enlarged liver) in disease states, but it can be physiologically normal. Yet, disease states have to be ruled before saying it is a normal physiological state. My first question would be do you have any symptoms that brought you to your physician? If not, diseases have to be ruled out. Diseases of the liver can be seen as intrinsic (internal causes) or extrinsic (external causes).
The intrinsic causes of liver disease are autoimmune caused by genetics abnormalities and can be identified by blood tests. In fact, do you have any abnormal liver function tests?
The extrinsic causes of liver disease include hepatitis in which blood tests for Hep A, B, C can be done. Also, alcohol and drugs contribute to liver disease and since you are a 25 y/o female with unknown past medical history, the most common cause would be the use of oral contraceptives.
Followup on blood tests would include an abdominal ultrasound with good sensitivity of finding abnormality.
Thank you for your question.