First experience with dumping....

could have been the eggs or the mustard. I'm four years out and still get that with fatty meals, falafel, sauerkraut - a few others, too, that I'm sure I'm forgetting. The acid or the fat or the spices or SOMETHING in those things is really hard on my stomach.

You've gotten all the good answers already, but just to maybe confirm some things I'll add a tiny bit.

So dumping syndrome is less about the vomiting and/or diarrhea and more characterized by weakness, rapid or irregular heart rate, cold sweats, and dizziness. It generally comes on within 30 minutes of eating the offending food.

Basically you'll want to curl up on the floor, regardless of where you're at, and hope for death. And yes, it really is that bad.

It sounds to me like you're dealing with a food that maybe your pouch wasn't quite ready for, as the others have said. This doesn't mean you aren't a dumper. It just means that this wasn't a dumping episode.