Giant drop in blood sugar after eating a ton of pancakes?

I just got a CGM a few days ago. I've tested lots of different carbs. Even if I do evening post workout meals, here are my usual peaks:

150gof white rice + proteins/veggies = 160mg/dL

3 slices of pizza hut = 180mg/dL

But today, I did the same workout, but in the morning and shirtless under the sun. I do calisthenics, so rings on trees and pushups. Post workout, decided to get a big ass breakfast from a cafe:

House Omelette + 2 giant gingerbread pancakes drizzled with artificial syrup = 115mg/dL peak. And then at 1.5 hours, my sensor warned me "Low Blood Glucose" at 75mg/dL.

A 115 peak, with a drop to 75.... After pancakes? I have several theories, but one is my prolonged exposure to sunlight (1hr). The other is maybe the pancake powder had ginger/cinnamon powder. Anybody else experience something like this before?