I don't really have any answers for you, but glad it is all being investigated, as it should. You'll find the most unexpected things spike sugars, so am glad you're testing and discovering too. Hang in there! It's confusing at first but then you get to know what you can and can't eat or drink. I'm continually disappointed that my numbers go up a lot after my three times a week exercise class. We're 40+ year olds, so it's not exactly cardio or anything massively strenuous (!).
For me, I was diagnosed T2 when I was 'young' - 36 - and had no symptoms and a normal BMI (around 22), but HBA1C of 46. My doctor was good and did all the testing for T1, which I wouldn't have had the foggiest to query otherwise. In the 8 years since, I've had high HBA1Cs - topping at 88 twice - and lower ones of 48-55, which are still high but are accepted as okay by my GP. The really highs corresponded exactly to eating bread, biscuits, chocolate, fruit on a regular but not binging basis and bad symptoms. The lower numbers were a low carb but not keto diet, which had hardly any symptoms. I'm trying strict keto at the moment, and it's brought my finger prick numbers down a lot. And also I have more energy and am sleeping less and waking up earlier, which has surprised my entire family!
It's taken 8 years but I've finally been diagnosed with a genetic disease that's responsible for my diabetes. Because of it I can't take metformin, so am personally trying to stay off the other meds for as long as possible.