What to trust Google shortner analytics or Facebook insights ?

hello everybody,
I do social media posting everyday on Facebook, Linkedin, Twitter, and Google+. And since two weeks Iam using google shortner for tracking the engagement to the post I shared.
But when I check Facebook insights it shows 2 clicks on the post and Google shortner analytics shows 26 clicks.

So which data should I use to track?

Use bit.ly because goo.gl is not good. He track bots ( fake traffic ) that came from share.
Share a link and look on analitycs and you will see trafic from facebook home. USA