The most recent "long term release" is version 2.18.18 (https://qgis.org/en/site/) so you probably should update your version as soon as you can. 2.14.2 is a pretty old version now.
If you still have a problem after updating, try to figure out exactly what you did just before it crashed. If you can repeat the crash with the same circumstances, it's probably a bug and should be reported.
How you report a bug can also be found on the QGIS web page.