IP+UTserver

Well i have been trying to make a dedicated server for quite some time so i could play around with it and learn about all the different settings. I have learned how to use most of these such as ASC and NexGen, and I have now learned how the WebAdmin works thanks to FN. However, whenever i go to make a dedicated UT server and try to log into the WebAdmin i am never allowed in. Lets say i am running off the IP 12.345.678.9 (which i got from Command Prompt /ipconfig) through the default port "80" I type in the correct information into the url bar and nothing happens. Lets say that then i went to one of the many ip finding websites and it tells me my IP is not 12.345.678.9 but 98.765.432.1 instead so i type that in and atleast something happens this time. It pulls up with the Username and Password box. So i enter in both, but instead of being directed to the webadmin page i am moved to the linksys controle area. Inside the linksys main page it even says my IP is 12.345.678.9 but for some reason when i type that in i am not pulled up to the correct page. After seeing that i apperently had 2 IPs? I decided mabey i would look to see if my computer had a proxy on. So i went to internet options, connections tab, and LAN settings to see that know infact i had no proxy running just as i had thought.

Any ideas to why i cant get Webadmin to work and why i seem to have 2 IPs running at the same time? O.o