What can I do if I am a screenwriter and didn't give permission for production to use my work?

I am a screenwriter and recently resigned from a production. When I was brought on to the production March 1 2013 I was only asked to sign a confidentiality agreement. When asked about a contract the producer/creator of the web series stated that I did not need a contract because she was not only bringing me on as a writer, but also as a partner/executive producer. Unfortunately, being new to the business I continued to write, develop, and put money into the project without a contract. As time went on I became more and more uneasy about writing without a contract and I insisted that a contract stating my responsibilities and commitment to the project. My request was never granted, every time I brought it up another excuse was given, and another week would pass. On June 18 2013 after a production conference call, I felt the need to submit my own contract, for the protection of not only my writing, but my integrity as a writer. My contract was denied, and I subsequently resigned on June 21 2013. In my resignation I stated the following: Upon my departure, I do not give permission to productions, or anybody else affiliated with it to use anything that I have written. This includes all 4 promotional videos (concepts and actual scripts), storylines and names for Sam and Aiaki. Storyline dealing with Morgan, Arson, Max, additional goons, the development of the relationship between Murf, Bear and Andrea, the church controversy, and any other concept I may have come up with and put together on behalf of the first season of this show. As bad as it pains me to do this, I do see that this is what's best. I am asking that within the next 24 hours my picture and any information related to me be removed from the website, as well as the Facebook page. I ask that the promotional video be removed and the next one not be released. Again, I wrote them and do not give permission for them to be used.