Lois's reaction to Clark revealing that he's Superman was unexpected. In most stories (and canon), she's upset with him. Laughing and not believing him (at least at first) is different.
Lois and Clark are moving fast in this story. I look forward to seeing how you explain it.
"Oh, you can’t help that," said the Cat: "we’re all mad here. I’m mad. You’re mad."
"How do you know I’m mad?" said Alice.
"You must be," said the Cat, "or you wouldn’t have come here.”
- Lewis Carroll, Alice in Wonderland
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