Try to set boolean value, so that in the first press make it false inside the mouseclick event code.
For every mouse press event check the boolean. For the first time the boolean will be true and the mouseclick event will occur, inside the statements change the boolean value as false. So that for up coming mouseclick event will check for the boolean and comes out executing nothing.
declare the boolean variable (flag) globally with value true.
Hope it will satisfy your need.