London-based aspiring writer of fantasy epics for grown-ups in the style of Robert Jordan and Steven...
Very nice, and endears the reader to the protagonist.
Davin was quiet for a moment, then nodded. Then he realized that she couldn’t hear that over the phone
Be careful with using colloquial language during narration. It can come across as lazy or inconsistent when the rest of the narration is more formal. If you want to go informal and colloquial, then by all means, go for it - just try not to do half one way and half the other!
Redundant. Again, try not to spoon-feed the reader with over-descriptions. The not-serious tone was apparent from the smile already - don’t doubt your ability to do more with less!
which told Davin he wasn’t being too serious
This needs rephrasing - it’s a bit awkward and mixes the he/you pronouns in a way that I’m not entirely sure makes sense.