Is this legal or am I doing nothing wrong?

I went to a pet store and noticed that the animals were starving and some were dead in their cages, and I took pictures of this. Now I have a cause on facebook called "boycott such and such" pet store with the photos on it, and I'm already generating some support. Is this slander or something? I cant get sued can I? I'm just trying to get the word out about how terrible this store is treating their animals so they go out of business, or reform their ways. I've also contacted a local news station and given them the link to my facebook page and told them all about my visit there. I'm not doing anything thats going to get me in trouble am I? I don't care if it miffs the store owner, I actually hope it does, I just don't want them to be able to take legal action.