Yep that sounds fair if there is a general credit which implies your photo belongs to the newspaper's photographer I would complain as well. I would check what will happen with the photo once the paper has finished with it, generally if it's a printed photo it's kept until the person that sent it in comes to collect it. I'm not sure what happens with digita images.

Most times with announcement the photographer doesn't get credit because the couple doesn't secify who it was. Maybe if you do any more weddings ask if you can be credited if they are going to display the photos anywhere?