--that, given the reports of what you said you've consumed, some of those half-hour and 1-hour readings are concerningly high. But it is true that people can have occasional high spikes like that, due to supplements, medications, activity level, content of meal, or even stress (which certainly raises blood glucose levels temporarily) without being diabetic.

I do agree, though, that a longer (and stationary!) glucose tolerance test with 1/2 hour spaced draws and insulin levels done concurrently may give you more insight into what's going on. Yes, it's boring, and yes, it makes you feel like a pincushion (it helps to alternate arms and fingers during the draws), but the patterns of results are often helpful to see whether insulin resistance is suspected and how severe it may be.