Why don't I dump?

I've only experimented with sugar on a few occassions and I know my dumping experience was't really what I expected.  I pictured I get so sick and run to the bathroom but instead I got super sleepy.  I felt like I had to lie down right then and there and take a nap. My sleepiness only last about 20 min and then I'm fine.  So maybe you have had an experience like that and didn't recognize it as dumping. 

Hmmmm...can't really say that's happened.  My biggest problem was a few months after surgery when I started eating "whole" meats.  Just a lot of pain or else it would come back up.