If you want to view your last test result, press the button on the front of Nima just once and wait 10 seconds. Your previous test result will appear on the screen.
The above method will work if you are on firmware version 2.2 or above. However if your Nima is on older firmware, then you have to rapidly press the Nima button twice. Please note that this double press may run a risk of running a test, so ensure it is rapid. (think click click vs. click and press)