Here’s her explanation of the difference:
“bǔ yáo niǔniǔniēniē” jiùshì bǐjiào kǒuyǔhuà de.
“不要扭扭捏捏”就是比较口语化的.
“[the first way]” is relatively colloquial.yǔqì méi nàme zhòng.
语气没那么重.
The tone of voice isn’t that serious.“bú yào niǔniǔniēniē” jiùshì yǒu yìdiǎn shēngqì de gǎnjué.
“不要扭扭捏捏”就是有一点生气的感觉.
“[the second way]” has a little bit of an angry feeling.
So there you have it, straight from a native speaker’s mouth. It opens up a whole new discussion called, “Well, how do we know what tones can be fudged to express feelings?” The short answer: we don’t, only they do.