This is the same issue I reported last night. @aitken.jared In the header of your site, the NextGen script declarations are missing a “/” in the URL concatenation just after the FQDN. See code from your page header below:
</script>
<script type='text/javascript' src='https://www.chessingtonbuzz.co.ukplugins/nextgen-gallery/products/photocrati_nextgen/modules/ajax/static/ajax.js?ver=3.9.2'></script>
<script type='text/javascript' src='/wp-includes/js/jquery/jquery.js?ver=1.11.0'></script>
<script type='text/javascript' src='/wp-includes/js/jquery/jquery-migrate.min.js?ver=1.2.1'></script>
<script type='text/javascript' src='https://www.chessingtonbuzz.co.ukplugins/nextgen-gallery/products/photocrati_nextgen/modules/ajax/static/persist.js?ver=3.9.2'></script>
<script type='text/javascript' src='https://www.chessingtonbuzz.co.ukplugins/nextgen-gallery/products/photocrati_nextgen/modules/ajax/static/store.js?ver=3.9.2'></script>
<script type='text/javascript' src='https://www.chessingtonbuzz.co.ukplugins/nextgen-gallery/products/photocrati_nextgen/modules/ajax/static/ngg_store.js?ver=3.9.2'></script>
<script type='text/javascript' src='https://www.chessingtonbuzz.co.ukplugins/nextgen-gallery/products/photocrati_nextgen/modules/lightbox/static/lightbox_context.js?ver=3.9.2'></script>
<script type='text/javascript' src='https://www.chessingtonbuzz.co.ukplugins/nextgen-gallery-pro/modules/nextgen_pro_lightbox_legacy/static/jquery.velocity.min.js?ver=3.9.2'></script>
<script type='text/javascript' src='/assets/js/vendor/modernizr-2.6.2.min.js'></script>
<!-- <meta name="NextGEN" version="2.0.66.27" /> -->