Have you replaced any British words with their American versions?
For example, switching out the word 'boot' for 'trunk', or ditching the word 'rubbish' for 'garbage'.
This is something I've noticed my 6 year old does pretty regularly. We went through a stage where 'sweets' became 'candy', 'holiday' became 'vacation' and 'courgette' became 'zucchini'.
That last one didn't happen but if you're still reading you've got my respect, or as the Americans might say '...mad props'.
I’m in Australia now and it’s zucchini and eggplant here, though in general words are much more like British English. No idea what’s going on with the pronunciation of “cache” here though - I work in tech and it’s mental how they say that. Like, Brits and Yanks are in full agreement about that word.
It's supposed to be pronounced as "cash" or "kaysh". Americans often pronounce it as cachet (ie. "ka-SHAY"), which is a different word with a different meaning. Needless homophone that introduces confusion.
I'm guessing that's been picked up by Australia in recent years, but not when I still lived there.