I've personally found that once you start treating your diabetes, everything changes. Not just your daily routines and diet, but also the way your body behaves. My inner temperature control has been on the fritz with no signs of stopping (I'm either freezing my butt off or so hot I start feeling sick, and the slightest outdoor temperature changes mess with this a lot), my periods have gone haywire, I sweat buckets with the simplest of activities where before I never would etc.
So far none of this is really any indicator of me doing anything wrong, it's just my body being jarred from however long I was in poor health suddenly becoming healthier. I suspect that if high sugars aren't an issue at night, it could be a UTI like Azure suggested, but this might also just be one of those diabetes things that happen to us once we take back the reigns. Stuff changes, it no longer makes sense, but here we are!
It's worth talking to your healthcare team about it, but I wouldn't worry too much!