Django on Nginx help needed

I am trying to deploy my website to aws ec2. It's in python/django and I want to learn how to deploy websites myself. I had some issues with aws's EBS so first I'd like to know how to do that manually. I decided to use gunicorn and nginx for this.

I can run the website using gunicorn on a virtual env and I created the following script in /home/ec2-user/gunicorn_start.bash:

#!/bin/bash

NAME="davidbiencom"                                  # Name of the 
application
DJANGODIR=/home/ec2-user/davidbien             # Django project directory
SOCKFILE=/home/ec2-user/virtual/run/gunicorn.sock
USER=ec2-user                                     
GROUP=ec2-user                                    
NUM_WORKERS=3                                     
DJANGO_SETTINGS_MODULE=davidbiencom.settings             
DJANGO_WSGI_MODULE=davidbiencom.wsgi                     

echo "Starting $NAME as `whoami`"

# Activate the virtual environment
cd $DJANGODIR
source /home/ec2-user/virtual/bin/activate
export DJANGO_SETTINGS_MODULE=$DJANGO_SETTINGS_MODULE
export PYTHONPATH=$DJANGODIR:$PYTHONPATH
# Create the run directory if it doesn't exist
RUNDIR=$(dirname $SOCKFILE)
test -d $RUNDIR || mkdir -p $RUNDIR

# Start your Django Unicorn
# Programs meant to be run under supervisor should not daemonize themselves (do$
exec gunicorn ${DJANGO_WSGI_MODULE}:application \
--name $NAME \
--workers $NUM_WORKERS \
--user=$USER --group=$GROUP \
--bind=unix:$SOCKFILE \
--log-level=debug \
--log-file=-

This runs fine I believe as there are no errors. Next I install nginx and start the service. I confirm it's running as I get the welcome page. Next I do the following:

1. Go to /etc/nginx/nginx.conf and add the following to http

   include /etc/nginx/sites-enabled/*.conf;

I then create two folders in /etc/nginx/ sites-available and sites-enabled. I create a file davidbien.conf and enter the following inside(UPDATED):

upstream app_server {
# fail_timeout=0 means we always retry an upstream even if it failed
# to return a good HTTP response

# for UNIX domain socket setups
server unix:/home/ec2-user/virtual/run/gunicorn.sock fail_timeout=0;

# for a TCP configuration
# server 192.168.0.7:8000 fail_timeout=0;
}

server {
listen 80;
server_name 35.176.185.50;

#Max upload size
client_max_body_size 75M;   # adjust to taste

location /static/ {
    root /home/ec2-user/davidbien/static;
}

location / {
  # checks for static file, if not found proxy to app
  try_files $uri @proxy_to_app;
}

location @proxy_to_app {
  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
  # enable this if and only if you use HTTPS
  # proxy_set_header X-Forwarded-Proto https;
  proxy_set_header Host $http_host;
  # we don't want nginx trying to do something clever with
  # redirects, we set the Host: header above already.
  proxy_redirect off;
  proxy_pass http://app_server;
  }
}

I save this file and run the following command:

ln -s /etc/nginx/sites-available/davidbiencom.conf /etc/nginx/sites-enabled/davidbiencom.conf

After this is done I restart nginx and I when I enter the ip address I get 502 bad gateway error.

What could be wrong here? Thank you.

EDIT: Here's the error logs from var/log/nginx/error.log

2017/11/10 22:26:27 [error] 27620#0: *1 open() "/usr/share/nginx/html/favicon.iicon.ico" failed (2: No such file or directory), client: 2.96.149.96, server: $localhost, request: "GET /favicon.ico HTTP/1.1", host: "35.176.185.50",referrer: "http://35.176.185.50/"

EDIT 2: Here's the etc/nginxnginx/conf file:

http {
log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                  '$status $body_bytes_sent "$http_referer" '
                  '"$http_user_agent" "$http_x_forwarded_for"';

access_log  /var/log/nginx/access.log  main;

sendfile            on;
tcp_nopush          on;
tcp_nodelay         on;
keepalive_timeout   65;
types_hash_max_size 2048;

#include             /etc/nginx/mime.types;
#default_type        application/octet-stream;

# Load modular configuration files from the /etc/nginx/conf.d directory.
# See http://nginx.org/en/docs/ngx_core_module.html#include
# for more information.
include /etc/nginx/sites-enabled/*.conf;

index   index.html index.htm;

server {
    listen       80 default_server;
    listen       [::]:80 default_server;
    server_name  localhost;
    root         /usr/share/nginx/html;

    # Load configuration files for the default server block.
    include /etc/nginx/default.d/*.conf;

    location / {

# redirect server error pages to the static page /40x.html
    #
    error_page 404 /404.html;
        location = /40x.html {
    }

    # redirect server error pages to the static page /50x.html
    #
error_page 500 502 503 504 /50x.html;
        location = /50x.html {
    }

    # proxy the PHP scripts to Apache listening on 127.0.0.1:80
    #
    #location ~ \.php$ {
    #    proxy_pass   http://127.0.0.1;
    #}
 # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
    #
    #location ~ \.php$ {
    #    root           html;
    #    fastcgi_pass   127.0.0.1:9000;
    #    fastcgi_index  index.php;
    #    fastcgi_param  SCRIPT_FILENAME  /scripts$fastcgi_script_name;
    #    include        fastcgi_params;
    #}
# deny access to .htaccess files, if Apache's document root
    # concurs with nginx's one
    #
    #location ~ /\.ht {
    #    deny  all;
    #}
}