Help...water heater question

your friend wrote:
So I should be good if I just turned off the water. That tank is still filled with water right?

As long as you had water in the heater it will be OK. If you drained the heater or drained the lines and it pulled out enough water from the heater, the damage is already done. It takes about a minute (or less) for the element to burn out without water. If the element burned out, it probably tripped the breaker or the circuit is open, no worries.