I have a Maytag series 9 electric water heater is about 9 years old. We had a problem with our well pump 2 days ago and water was turned off for a day. Once the water was turned on. The water was extremely hot last night. Now the water is "luke cold". NO ONE TURNED THE water heater off during the water problem. Is it possible that we killed the heater? I reset the circuit breaker, reset the heater breaker. Dumped water from tank and flushed system. Its like the system is dead. What's next? A new unit?

The little red button(thermal disc) may need to be pushed in to reset?
An Electrician will check for power through the Thermal and thermostat, then down to the Element, If you have voltage to the element and it is not heating, the element is likely open.
If no voltage is at the element, then the element may be OK.
Did you empty the water with the Breaker ON?