Yes, Florida is an at-will employment state. Generally, that means an employer can terminate an employment relationship without cause. However, that doesn't give the employer free rein to fire workers in all situations.
Wrongful termination can be hard to prove because you have to determine the specific motivation of the employer. You have to show that it was an illegal reason that prompted them to terminate you. However, you can prove this by methodically building your case. Witnesses, records, emails, patterns of hiring and firing can all be instrumental in proving your case.
A wrongful termination attorney can help you with this complex process. They can pour over the details in order to explain exactly what happened and present the information effectively.