Thank you for posting a link to your site. I examined the page source code and it appears that the pinit.js file is being called more than once. This can cause issues. Do you have other social plugins installed? If you do then you can try deactivating those to see if the problem is resolved.
On another note we will be releasing a new version very soon that will allow you to deactivate the pinit.js being called from our plugin so that errors like these should be less common.
Let me know how it goes and I will be glad to continue helping you.