Do I have a case to proceed with a sexual harassment/discrimination/or retaliation lawsuit?

I made a complaint of sexual harassment from my supervisor to my employer. I never wrote out a formal complaint, but he believed me, due to the fact that other employees have complained about the same guy before. But, the supervisor was kept his job, and I was transferred to another department. 2 years later, I was fired. I received no severance, and was not entitled to unemployment. According to my co-worker, I was fired because of the sexual harassment complaint that I had made two years ago. This doesn't make sense to me, but I believe I was discriminated and retaliated. Do I have a case, even though I have no concrete evidence?