Describe Charlie's expression at third level?

Grand Central Station of New York has two levels namely New Haven and Hurtford. There does not exist any Third Level. It is only the imaginary discovery of the narrator and his psychiatrist, Sam who calls it a waking dream— wish fulfilment. One night he took the subway from Grand Central Station which was faster than the bus.

On reaching there, he went down the steps to the First Level. Then he walked down another flight of stairs to reach the second level. He got into an arched doorway and was lost in a wrong corridor. He kept in walking along the corridor which went turning left and slanting downwards. At its end, he went down short flight of stairs. Then he came out. He found himself on the third level. For a moment, he thought he had again come back to the second level. There he got surprised to see everything different from old fashioned. It made him believe that he was actually standing at the Third Level.