domain mismtach

Hello, I am unable to view anything other than the homepage.
this is because i have edited the wordpress site URL to point to the amazon ec2 instance id – example “ec2-xx-xx-xxx-xxx.compute1.amazon.com” so all wordpress files are in relation to the above mentioned address.
now i assigned an elastic IP address to the amazon ec2 instance which released the previously assigned public IP address. so now the server is hosted on the elastic IP while wordpress still has the site pointed to the public IP address which does not exist now. please advice how i can point wordpress to the elastic IP and atleast login. once i login i can changes the links for other pages to point to the new elastic IP.

in dire need of help.

Regards,

Mihir