If you don't have anything blocked port wise and you are letting the DHCP assigning the lan ips and your system is showing a lan ip but not the wan connection on your lan... then it might be a simple issue of renewing the network connection as to update your computer with the current ip address of your router... sometimes the router and a pc can get out of sync...
Go to view network connections if you are using windows and renew or fix your connection...
Hope this helps you out...
Later,
.