If the “<div>” tags and css classes in your template are not used properly then it can mess things up but I don’t think this is the issue here.
Can you post a link to your page?
Also, a good test is to disable all the plugins except the well known ones (e.g Akisment, All in all SEO etc) and switch your theme to the default wordpress theme then see what happens. If the button appears then you can start to activate the plugins back and see which one causes the problem. There are too many plugins and themes out there that are not coded according to WordPress coding standards and it causes more problem most of the time.