I have recently moved into a home with a lot of plumbing problems. Tonight I noticed a warm spot under the tile in my upstairs bathroom. I know that's a tell tail sign of a slab leak downstairs, but what could it mean upstairs? Help!

I noticed a warm spot under the tile in my upstairs bathroom. I know that's a tell tail sign of a slab leak downstairs, but what could it mean upstairs? Look for signs of moisture under the warm spot on the ceiling.
To check you could shut off the water to the hot water heater and see if the warm spot cools down or go out and check the water meter. To check for a hidden leak go out to the water meter, look for the little pointer or triangle below the read out. With all your fixtures shut off you should not see the little pointer moving. The faster it moves the bigger the leak.Look on the meter dial, (see image) The large hand measures in tenths of a gallon. One complete turn equals ten gallons. On a pump system the gauge should not fall with every thing off and the pump up to pressure and not running. Let me know what you find. Good luck, Tom