Tesla Model 3 High Voltage System Warning

[Strocky]

Driving to the airport last week and coming off the motorway just before the turn off and the red light of doom came on with a High Voltage System warning about the rear inverter losing power and that the car would come to a stop

I stopped the car, locked it and opened it and the message cleared so was able to drive on full power to the car park
Back from holiday drove it back home around 30 miles at a steady 60mph and no further warnings

Has this just been a glitch or should I get Tesla Roadside involved?

I assume if it's a drivetrain issue then it's covered under their 100,000 miles or 8 years warranty?
I'm not the original owner and purchased it 2nd hand from a dealer