In search of revision to 555 Monostable circuit to create a resettable timer
The 555 timer can source current as well as sink current.  You currently have it wired to source current.
While the output is high after being triggered, the 555 is supplying current to your LED.  You could wire it so that the anode of your LED is connected to the supply rail and the cathode connected to the 555 output. You will of course still need a series resistor.  This way, while the output is low, your LED will light, then once triggered and the output goes high, your LED will extinguish until the time period has expired.
The 555 I just looked up was able to supply 200mA and sink 50ma, so it is able to cope with sinking the current required for an LED.
The website I took this image from has a tutorial about this -