The author has admitted to it being fake, so you all can relax now.
"Creator Bruce Banit confessed to mocking up the video using special effects..."
"However, the visual special effects company operator 'fessed up to creating the video himself using very convincing CGI.
"Okay. So, yeah. I don't really have a spider in my ear," he wrote in a blog post, adding that the inspiration for the 14-second clip came after a “hell-of-a case” of swimmer's ear."
a spider will never enter your ear or your mouth or any other opening in your body, unless you're dead. they actively avoid large threats like humans, and have no want to do something just because they know it would freak you out. heh.