No, there is no requirement for the officer to provide a test sample in front of you. There are steps they must take to ensure the device is functioning correctly but these would be done prior to use, typically at the start of shift.
First, the officer must ensure that the device has been calibrated within the past 14 days. Calibrations are performed by trained officers using an alcohol solution to ensure the device is obtaining correct readings. Many officers will also provide a test sample at the start of the shift to ensure there are no obstructions and the device is capable of obtaining samples. Lastly the device itself performs a self-test on startup and prior to each test. It will also display an error if it detects any type of sensor fault, etc.
If you blow a warning and truly believe theres been an error, you CAN request a second test with a different instrument. The officer can then get a different roadside screening device or take you to the station to provide a sample into an intoxilyzer. This isnt something Id suggest doing lightly though, because if the second reading is over the legal limit, youll then be facing a criminal charge with an immediate 90 day suspension instead of an administrative 3 day suspension.