There are several laws that apply here. If you worked more than 1250 hours in the past 12 months, and your employer has more than 50 employees, your employer is required to allow you to take family/medical leave -- and return you to the same job when you return.
If your employer has more than 5 employees, and the injury qualifies as a disabilityy under CA law (many injuries do qualify) the employer is required to provide you with "reasonable accommodation," including time off from work to recuperate, and is required to engage in the "good faith interactive process" to return you to work.
Your employer may have violated several laws by terminating you. You should speak with an attorney immediately if you wish to pursue this further.