Do not ignore symptoms that may be due to low or high blood glucose. If you have symptoms that do not match the Sensor glucose reading or suspect that your reading may be inaccurate, check the reading by conducting a finger stick test using a blood glucose meter. If you are experiencing symptoms that are not consistent with your glucose readings, consult your health care professional.

Why does the Sensor log data every 15 minutes? Why not every 5 minutes?

The Sensor has limited storage capacity to keep the Sensor profile small. In the interest of preserving 8 hours for a typical overnight period, 15 minutes was chosen for the interval.1

Reference

1. FreeStyle Libre flash glucose monitoring system User's Manual.