Need help with an LED flash circuit
If you just want to use 555 devices then you could wire the LED to a 555 in Astable configuration and use a 555 in Monostable configuration (as your diagram) to control the RESET (pin 4) of the Astable 555. So the monostable enables the astable for the required time for 2 flashes.

See here for a 555 tutorial.

Also:
You need a resistor in series with the LED. 100 to 300 Ohms or so depending on the brightness you need.
C2 is very large. You should reduce it by a factor of 100 and increase R1 correspondingly.