I am in the same boat. Drinking 75g of Grape juice, I hit 135 within 1 hour then went down to 90 after 2 hours.

Did the same test with 3 slices of Pizza and a coke, hit 170 in 30 minutes! then 148 in hour 1 and 143 in hour 2, 108 in hour 3.

I definitely diagnosing myself as Predibetic. Don't care what my doctor says. (he says I'm fine cuz my FG is 97)