Hello and welcome to JustAnswer.
I'm sorry to hear about your situation and hope I can help.
It definitely seems like a wrongful termination and discrimination case to me based on your facts.
Since you were 'let go' on the exact date of your accident, that would definitely demonstrate that you were terminated due to having your disability and in retaliation for filing a workers' compensation claim, or potentially filing one in your case.
Also, as you seem to suspect, it appears that you were misclassified as an 'independent contractor' when you should have been classified as an employee.
In addition to pursuing a wrongful termination case, I suggest you make a complaint to the Department of Fair Employment and Housing for discrimination due to your disability in violation of the Fair Employment and Housing Act.
You can make a complaint using the instructions available online here:
The Department of Fair Employment and Housing will investigate your complaint on your behalf and either file suit on your behalf or issue you a 'right to sue' letter so you can pursue your claim against your employer through a private attorney.