" Oh, I've got a tummyache, make me some soup."

“哦，我肚子疼，给我做点汤。”

If the problem is in this area, your tummy or your stomach, you would say " I've got a tummyache" or " I've got a stomachache" .

如果问题出在这个地方，你的肚子或你的胃，你可以说“我肚子疼”或“我胃疼”。