Upstream response header error with LEMP stack running Wordpress
I'm running a wordpress site on my Ubuntu 13 droplet, configured with LEMP. On the wordpress side I've just installed a ecommerce plugin, and all of a sudden I'm getting error on the nginx side of things (this is from the nginx error log):
2015/03/03 20:56:43 [error] 5059#0: *23 upstream timed out (110: Connection timed out) while reading response header from upstream, client: xxx.xxx.xx.xxx, server: meshconsultants.ca, request "POST /?pageid=906&payment-mode=manual HTTP/1.1", upstream: "fastcgi://unix:/var/run/php5-fpm.sock", host: "meshconsultants.ca", referrer: "http://meshconsultants.ca/?pageid=906"
I've gone back over the installation tutorials and I don't see anything wrong. Any thoughts? I can post my config files if needed.