Chris;

It sure sounds like an intermittent failure of the bulb failure sensor...IT controls the bulb failure light, and if no lights were ON at the time, but it was turning on the failure indicator...that seems pretty clear. The intermittent condition will probably occur again, and possibly get worse if you let it go.

Bulb failure sensors are not cheap...but if you're confident working with electronics and soldering, repair is possible...I suggest removing the sensor, carefully extract the guts from the case, and inspect the solder joints on the PC board with a lupe...look for questionable/compromised solder joints (sometimes a circle of oxidation around component lead is visible...this is a pretty good hint). Resolder, reassemble, reinstall.

Good Luck