Nothing says "happy new year" then your website developing issues! Part of the website was built from a template and it seems the designer of the template decided to host a whole load of code from his website. He's now changed that code on his website and as a result broken everyone's website that used his template (I've just come from the template website and everyone is experiencing this and as you can imagine, are not very happy).
I'm looking into fixing this, so please bear with me. I'm also looking at changing all the back end code so everything is hosted off local files I control rather than remote files on his website, so this won't happen again in the future hopefully once I've done that. This will teach me to use a template!
I'll update this post once I've sorted everything.