Can I be forced to sign a new contract voiding out my present one?

I signed a one page independent contractor agreement with a home care agency last year. Recently I was handed a new 5 page contract to be signed the following day by Fri 5pm or I could not report to my client. The owner said it was short notice because he was just notified he had to have new contracts because he was audited. My present contract(which by date is still valid) states that at the termination of my contract either party must inform in writing 15 days before contract ends if either party wishes to terminate the contract. I refused to sign because I wanted the contract looked over. The owner said I would not be able to work until I signed and I found out a couple hours before the deadline if I waited to Monday my full time client of several months would be reassigned to another contractor. I did not sign because I felt like a had a gun held to my head but I was told out of 100s of home aids I was the only one not to sign. What if any are my legal rights?