Langstraat, you should be fine. The light comes on way before you should be doing any damage. As a quick check though since the sensor is only on one side of the car (not all 4 wheels), I would look at the rotors on all 4 wheels and see if you spot any signs of damage happening to the rotors. May want to see if you can reach in to the back side to run your finger across the rotor (make sure to do this before you drive the car, not afterwards, rotors will be very hot). if you feel any ridges, then not driving the car would be the wise thing. If all feels smooth, then you should be golden.

 

It typically triggers with about 4mm of pad material left so in reality you have a few thousand miles of typical driving at least - and maybe more. There are two sensors - one on the rear right hand wheel (for rear brakes) and one on the front left (for front brakes)
Only get the pair that is needed done!
Also they will say they have to change rotors instead - ask them to measure and compare to spec. Typically they should last 2-3 sets of pads but seems like a waste to replace them if they are not yet worn

 

 

If my memory is correct the minimum rotor thickness is stamped on the rotor edge.