A week of typhoid fever can cause mild hepatomegaly?

Of course: I'm more concerned with how you feel, and if there's any reason to think you were allergic to any medications you may have taken for this illness. Sometimes "mild hepatomegaly" merely reflects a new examiner's observation -- the liver's position, shape and even size vary a lot from person to person.

Yes: Liver and spleen can enlarge in typhoid fever.