The 0.022 is the approximate voltage I get by the multimeter, 0.023390067 is not rounder.
Yes, but your schematic says 0.22V, not 0.022V.
And as I stated in the schematics, r3 and r4 should give a voltage ~ 0.045V
No, they give a voltage ~0.455V.
You are also not really working within the allowable common-mode range of this device. If you look at the "Linear Input Voltage Range" parameter on the datasheet you see that it expects the minimum input voltage (at pins 2 and 3) to be about 1V above ground.
The Gadget Shield
: accelerometer, RGB LED, IR transmit/receive, light sensor, potentiometers, pushbuttons