Was my reason for getting fired a criminal act and do I have a case?

I along with another employee chose to prank call our site director and his wife (the company medical coordinator). The prank was computer generated and recorded on a personal account on a prank web page. Nothing was said about work or any of the residents that the company offers a service for. The other lady that was in on the prank told on me for doing the prank but never told that she was in on it as well. I wasn't questioned about this or told that I was in trouble until the day I got terminated. I admitted that I had done the prank and thought it was no big deal. I was told that I had commited a crime and that I was lucky that they hadn't call the police on me. I was in shock and forgot to mention that the other lady was in on it. This incident happened on a Monday and I got fired on a Thursday. All the other residental coordinators knew that I was getting terminated on Thursday but me. I was also told that if I tried to apply for unemployment that they would fight me for it and that I wouldn't be getting any of my vacation or sick pay (I did get my vacation only). I have sent the excutive director an email explaining what happened and I got no response. They won't listen to me about the other lady being in on it. I also witnessed her forge state documents the same week that I was fired, but the company will not listen to me. I am being made out to be a villian and I'm not. I feel like I am being discriminated on. My boss told all the other coordinators the day that I got fired not to come in until I had left the building so my reason for being fired was not kept confidential and I feel like the other lady should be fired as well. I had never been written up or had any warnings that I was a bad employee. I think the site director took the prank personal and just took it out on me. Do I have case of any sort? I do have more details if needed.