LIkely, you are an "at will" employee. An "at will" employee means, this is an employment relationship without any specified duration of time. This means you can terminate your employment with or without notice and the same applies to your employer. On the other hand, you may be a contractual employee we're by the employer and employee will be bound by contract for a specified period of time. So ask yourself this, did you sign a contract with your employer to work for a specified period of time? If no, your employer can terminate you without cause, so long as the termination does not violate certain statutory rights. For example, termination based on race, national orgin, gender, sexual orientation. Based on your facts, you would not have a viable cause of action for wrongful termination.
Unless you had an express agreement to the contrary, you were an at will employee. As such, you could be terminated for any reason, or for no reason at all. Certainly refusing to carry out a lawful request is a legitimate basis for termination. Your employer had no duty to treat you equally, or to give you warnings. There is nothing in your post that would suggest you were treated unlawfully.
Furthermore, there are statutory provisions that require you to bring a lawsuit within a certain period of time before the opportunity is lost forever. The anti-discrimination, harassment and retaliation statutes generally require you to make a claim within a year or less to preserve your right to sue under them. The common law wrongful termination lawsuit has a two year statute of limitations. Depending on when it was in 2012 that you were terminated, the time to file that lawsuit may also have passed.
The good news, I suppose, is that you did not have a claim to begin with, so no rights were lost.
Good luck to you.
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