Was using a power drill on a gfci outlet and power suddenly stopped. The trip light did not go on on the outlet but the test button cannot be pushed (means no power, correct?) I took off the gfci and tested the incoming wires - no power. I've checked every room in the house for a tripped gfci but there aren't any. I went to breaker panel and no breakers were tripped. I tested each breaker and they are all outputting 120 volts. The breakers are very poorly labeled and I can't tell which one goes to the gfci. Is there a way to pinpoint which breaker runs to the gfci? Can there even be a problem with the breaker if it is outputting 120 volts?
Are there any other receptacles or lights with no power? Presumably there are other receptacles on this same circuit.
You say no power at the incoming line to this receptacle--presumably meaning no hot. So a connection of a hot upstream has gone bad. Do you have spring "backstab" connections to the receptacles? If so, change them to the side screw. (If you have backwire connections secured by the screw that is fine.)
In any case, check each receptacle in the circuit from the non-working one going back towards the panel. Use a plug-in circuit tester or a multimeter. It will tell whether there is no hot or no neural at each receptacle.