Ok, well, my problems have been resolved...problem is that I'm not sure precisely why/how.
I did two things:
1. Added --> include /etc/nginx/mime.types; to my location file.
2. Went into Moodle and purged all cashes.
Everything looks perfect now! I'm not sure which of the two fixed my problem but I'm glad it's fixed. Now I need to go through the methodical process of making sure my instance of Moodle is safe and secure. Being very new to Nginx, I'm afraid there may be security holes that I'm not aware of...hopefully not but it's better to be safe than sorry.