Equal Work opportunities for Medical Marijuana Card holders

I was hired on a job that requires drug testing. I explained I have been prescribed a medical card and was completely honest about drug test. The boss said i was fine I took a drug test, they made personal copies on file for there company so knowing I had my card but let me work anyway just to fire me when my drug screening came back positive for thc. I want equal rights a law that would protect card holders in the state of florida from being terminated from a job unless they are caught smoking during hours a law called "off-duty medical use" that would protect card holders as such if they didnt smoke on the job! I hope this can go somewhere because I'm 21 years old and had a great job I liked doing, mention it was for my kids if not anything I just dont think it's right. How can people be prescribed opiates that will impair them 50x worse than cannabis. Just keep in thought of the issue we have been facing in this country for a completely natural substance that is beneficial.

Thank you from Cam and Fam !