How does Nick's attitude change during his talk with Gatsby during the start of Chapter 4 and does he really believe the words that Gatsby said about himself?

[James]

Previously, Nick considered Gatsby was a person who had a lot to talk about because he experienced a lot, but later on he found that Gatsby failed him, he was just a boss who had a lot of money. "So my first impression, that he was a person of some undefined consequence, had gradually faded and he had become simply the proprietor of an elaborate road-house next door." (64)Gatsby as a Nick was asked to talk about what person Gatsby was in his own mind, but he was embarrassed and did not know what to say. So he just paltered and Gatsby interrupted him. The truth is, the experience that Gatsby said about himself was kind of ridiculous that Nick had to recover his facial expression.