Probably not. In Florida, you are an at will employee and an employer may take action for no reason, a good or bad reason, fair or unfair, factually correct or incorrect. Absent discrimination based on gender, race, religition, national origin, disability or pregnancy you likely would not have a claim given the facts you provided.
The demotion may be actionable if you can demontrate that it was done for a discriminatory reason, such as your gender. I would recommend you contact counsel in your area to look into filing a Charge with the EEOC. Once that process is completed (by law 180 days), you could bring a civil suit if the facts support one.