lol it's wild how many people try to power through basic stuff like eating when they're in work mode. I see it all the time, that feeling of "just gotta finish this one thing" and then your body shuts down.
Yeah that sounds like a seriously bad mix. Your blood sugar was probably in the gutter, and being up that high is no joke when you get lightheaded. I get trying to push through a job, but man, you gotta eat something before you work on a roof. Could have taken a really nasty fall. What did you end up doing, just calling it a day?