I was editing the files at college, and the widget was working, but now that I have the file open at home it isn't working.
Here is the code:
<div align="center">
<a class="twitter-timeline" href="https://twitter.com/bethesda" data-widget-id="668826568299532289">Tweets by @bethesda</a>
<script>!function(d,s,id){var js,fjs=d.getElementsByTagName(s) [0],p=/^http:/.test(d.location)?'http':'https';if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src=p+"https://platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs");</script>
</div>
UPDATE: I fixed it by removing it and adding it again. No idea what was wrong, but probably accidentally deleted or added something.