Magento 1.9.1 Amasty Full Page Cache program Porto theme 

I noticed my web hosting company installed nginx on our server recently and while I appreciate their effort – it seems to be causing many problems:

1. I have noticed the front end of the Magento website has slowed down considerably since nginx has been installed.

2. It is creating problems on the back-end (in the Admin panel) where:

2a. I get an Error sometimes when I try to re-index: 502 Bad Gateway nginx

and

2b. It is randomly throwing me out of places within the Admin panel (for example when working with products) back to the Admin’s default page (the Dashboard).

3. After restarting the server (Graceful reboot from within the WHM) – I was getting the 502 Bad Gateway nginx Error for a long time after clicking on a specific product on the front page of the website (the front page was already loading).

This leads me to believe that nginx is not properly configured and it somehow clashes with the settings necessary for Magento.

Any suggestions?