Here's an exchange between me and DS (aged 21) after some nagging on my part to get him to confirm some dates he's free for a family event, and he's finally sent them:
Me: Thanks. I've saved them in the family calendar so you'll remember to keep them free until confirmed. [We use a shared online calendar]
Him: No worries!
Or this when he's coming home after dinner:
Me: Will you want any food later?
Him: Yes please - will be back about 8.30
Me: OK. Have put some aside for you in fridge.
Him: No worries!
In both cases this left me feeling annoyed? I felt as if I'd been doing him a favour and what I expected was more a 'great, thanks!' but what I got was a response telling me not to worry, as if I'd done something wrong?
Urgh. I don't get it?