What does pain in the lower right back and stomach pain mean?

I am not sure as i am not a medical student. But on an experience basis, when i suffered pain in lower right back for a long time which was too unbearable. In medical diagonsis i found to have kidney stones. Drink as much water you can,it works really, stone was out of my body without operation, because as per doctor suggestion i drink lots of water daily, as a result urine was passed with great pressure. stomach pain due to careless ness in meal, or also due to stone. Watch the colour of your urine. If its red or dark yellow,take quick diagonasis by doctor