#1 Go to
http://en.wikipedia.org/wiki/Reserved_IP_addresses#2 If on your computer you have one of those Reserved IPv4 addresses that is
used for local communications within a private network as specified by RFC 1918 then you are behind a NAT router.
#3 As how to check the IP Address on your computer, will that depends on the OS and Version.
Since you are on Windows 8, it is..
a) Press the Windows Start key to open the Start screen.
b) Type
cmd and press Enter to launch the command prompt.
Note: You do not need to click on anything on the Start screen—typing will automatically initiate a program search.
c) Type
ipconfig /all at the command prompt to check the network card settings.