Am I a independent contractor or employee?

Am working with a certain organisation for 2 years,3 months now. The contract says am an independent contractor. But am given work orders to do, works in their offices, paid the same per diem rate as their employees,am supervised by them,and paid wage less than the minimum wage of North Carolina, I dont have any controls on the work I do,follow all instructions from the employers,I work with their employees on daily basis,I use materials, office supplies of the organisation in carrying out of my duties which am assigned from time to time