Is it my water pump undate?

As I wrote last night, I have a Isuzu Rodeo V6 3.2L 4X4. I guess I misunderstood my husband. I talked to him this morning and he said that it did overheat but the gauges on the inside of the car wasn't showing that it was overheating. It wasn't spewing coolant but the coolant that was just filled up a couple of weeks ago is empty. Does anyone know what the problem is?