confusion

I am a little confused and annoyed. I thought that the first amendment authorized us with Free Speech? Right now I am not so sure. I know that I can make no threatening, obscene or deflamtory remarks. According to Wikipedia there are restrictions. Yes, I am aware of them, well some of them. Speaking publicaly outside a free speech zone. I hadn't realized there were zones. So where are the zones? I should be able to use my imagination and write these words down and publish them? I would not be using profanities, threats or divulging company secrets. So in the future I may be restricted form exploring my imagination and writing works of fantasy that do not comply with 'he who must not be named' moral codes. Where have we come from and where are we going?