I get that too from time to time. More often with workouts that involve rowing or situps. I find get it more often if I am working out on an empty or a too-full stomach. What makes me feel better faster is to walk or even lightly jog and take deep relaxing breaths. Lying down or "resting" just prolongs the discomfort, water usually doesn't help. Only once have I ever had it progress to puking though. To me it is a very similar feeling as the kind of cramping that men don't get, if you catch my drift, a cross between being constipated and getting punched in the gut.
Here's an informative (WFS) article: