What happens when you give a NR injection as a correction and not with food? This might be the only way to see if it is the NR causing a problem. I wouldn't think it would cause a tummy ache but maybe she peaks a high bsl before it starts working and that gives her a tummy ache? You could try testing 20-30 mins after eating and see. Maybe her blood sugar drops very quickly and that makes her a bit nausious? You might be able to use a short acting that has a bit of a different profile to improve her comfort level.