On your router, I doubt if Port Forwarding is set up correctly. Also note that, the way you access your webserver from outside is important - do you hit with port 80? And is there a rule in port forwarding section that routes all requests from port 80 on the public ip, to the port that the webserver is listening to?
And note that you need to access the Router's public ip, to access the web server via a router.
Hope this helps.