That's quite a moral conundrum. I'm glad that Lois is thinking about the consequences of her actions. If she tells him about the time travel, I think he'd believe her. He's undoubtably experienced enough weirdness to have an open mind, and I'm pretty sure he's monitoring her breathing and heart rate to tell whether she's lying. Not that she would know any of this, of course.

"It is a remarkable dichotomy. In many ways, Clark is the most human of us all. Then...he shoots fire from the skies, and it is difficult not to think of him as a god. And how fortunate we all are that it does not occur to him." -Batman (in Superman/Batman #3 by Jeph Loeb)