I don't understand my gas or lack of...

For some reason, when I'm traveling, I have a gut of steel and then get back and my system is out of whack for a few days.

Hmm. Maybe it's your probiotic. It is working for the carby foods but not for the food you normally eat. You might try a different formula as there are different probiotics for different things.

is this even after about 6 hours? that is usually the time it takes my body to react to simple carbs  . .

Maybe think of it the other way around.  While you were eating that stuff, what weren't you eating that you normally do eat.  Make a list of stuff you normally eat but didn't that day.  There might be something that bothers you that you would never suspect.