Fired from job 3 weeks after announcing pregnancy

I was at my job for nearly 3 years and got fired for "not following rules" which wasn't true, 3 weeks after telling my bosses I was pregnant. Once I told my them, I could tell it was coming and I've seen how they have treated other employees in the past. I started to document everything. In the state of Louisiana employer can terminate without reason but with my pregnancy I wonder if I may have a case against them. I had amazing health insurance and wouldn't have had to pay a dime for prenatal care or delivery, and I can't get unemployement because according to them I wasn't following rules. I also worry about trying to find another job while being pregnant because I don't want to go through this again. Has anyone else gone through something similar?