1)An untradtional stomach ache, a pain so severe, that one is usually clenching arms around his or her stomach while bent over in pain. A pain not really able to verbally express it is that deep within.
2) A stomach pain so harsh it comes through from the gut and up to the stomach area.
1) Losing that game today is just as painful as a stummy ache.
2) You gotta hit him in the stummy, get him where it hurts.
A stummy ache is a combination of the words stomach and tummy. If you like both of the words, you shoud use the new term, stummy ache.
boy: Whats wrong Sally?
girl: i have a stummy ache.