Facebook, counts any and all interactions with ads as clicks. So if someone Expands a description, Clicks to read comments, Likes a post, Comments, Shares, or Likes a page. Facebook will count all of those interactions as clicks.
Website clicks are supposed to be clicks to your website, however, if your campaign is attached to a Facebook page they will usually count those as at least 2 website clicks. So you really cannot rely on any of the data Facebook provides, there is no way to know what it specifically includes.
Install Google Analytics on your website and use that as your true website traffic metric. Use your Facebook status as a relative measure, to compare the relative difference between campaigns, not an actual true metric. Remember “Google is your friend”, Facebook is your co-opted family and friends network