I signed a 'stipulation for settlement' at mediation under duress. My attorney became very verbally abusive before mediation to the extent that we no longer had a viable working relationship. With trial just around the corner, his surprise announcement of his expectation of sky-high fees (no written agreement) and no time before trial to get new counsel, I didn't feel that I had any choice but to settle. Can I undo this? The more formal agreement requires me to attest that I did NOT sign the agreement under duress. What can I do?