Xu Xiaoqing misunderstood Ning Fan's request for marriage, but after Ning Fan's persistent explanation, the misunderstanding was finally cleared. Xu Xiaoqing no longer let her thoughts stray.
Similarly, she stopped pestering Ning Fan. After all, she was only teasing Ning Fan out of habit and wasn't someone unreasonable. Realizing the matter was very important to Ning Fan, she didn't press further.
As for why Ning Fan chose to explain and not let the misunderstanding continue, it was because he was genuinely afraid of awkwardness in the future. He hadn't even considered such a thing as proposing; though it was embarrassing to admit, it was indeed the truth...
If he didn't take the chance to clear things up now and ended up stuck in an awkward situation later, it would be far worse!
After obtaining the Nine Souls Jade, Ning Fan shut himself in his room and began studying the seventh piece of the Nine Souls Jade in his hands.