First I can only suggest that you read this thread - since I already corrected how the no pin should be coded (at the very beginning of this thread) and there is NO class in it ...
Second, I can't imagine why you would have so many images that are 6000 pixels wide on your page. That is ENORMOUS - they're print resolutions that bog your site down tremendously in page load time and speed. They don't have to be that big for any reason unless you have a drive in, in your backyard, and people come to watch the posts on the movie screen ;-)
3rd, I dont know what "no pin it button' you're referring to - but I can tell you this - when you have a website you have to understand that your audience is viewing it from more than one browser and more than one kind of platform - Laptops, desktops, phones - AND Browsers= Chrome, Firefox, Safari, Opera, Internet Explorer etc - EACH of them have "pinterest extensions" that don't require or care if there is a pin it button on your site or not -
You do NOT need a JQuery anything - and if you don't know what you're doing with it, I can only suggest that you probably shouldn't be installing it.
It isn't necessary - it bloats your site more - it opens you to be vulnerable to people who will try to exploit your site thru JQuery etc etc
You can get a pinterest button FROM Pinterest - and you can add the no pin code - to the image you don't want to be pinned.
You could also try this plugin, its popular and safe - the developer is quite thorough, its simple and easy to use...
PS: You also have your pinit button set to pin a SPECIFIED image - but if I click my browser pin it - I can access every image on the page.