Featured Image Not Showing On Individual Posts

Since the 3.8 update (or sometime around there) my Featured Images on individual posts is not showing up. It does when I look at the home page and see all of my blog posts but not when I click on an individual post. As such, when I paste the link to an individual post to some place like Facebook, the site doesn’t grab the featured image.

Originally I thought it could be something with the theme so I activated one of the base themes like Twenty Eleven and the problem still exists. Any ideas on how to resolve this? Warning though, my knowledge on coding is very low so if you need me to paste any CSS anywhere I need specific instructions. Thanks!!!