As an at-will employee, you have only limited rights under Texas law. Even if you were fired for a bad reason, you have no recourse. Instead, you would need to show that you were fired for an illegal reasons. Here is a general discussion of the subject:
As for the other issues, the best place to lodge a complaint is with whatever agency licenses spas and health clubs, or else with your local district attorney.
The Texas Attorney General would be the place I would start to file a complaint about the licensing issues at the spa. If the AG is not the right agency to take your information they will refer you appropriately.
We could talk about possible defamation issues with the reason you were given for termination but those cases are very challenging to win and as a result are often very expensive to pursue. You can and should file for unemployment and let your former employer prove their own claims and try to move on.
I think you have asked this question twice, and I answered in the other discussion.
This answer is intended to be taken as general information and not as specific legal advice. You should always consult a qualified attorney and make him familiar with all the relevant facts in order to get proper legal advice. Every case is different, and they must be evaluated on a case-by-case basis. David N. Smith 812 W. 11th Street, Suite 201 Austin TX 78701 (512) 457-0100 defenseattorneysmith.com