The answer to your question is yes and yes. But, if you were smart, you would get yourself a divorce lawyer. Retirement funds are tricky matters that involve application of Federal Law.
The legal separation agreement can be contested because you were coerced into signing it. You may have spousal support rights from his retirement but the liability for the house will be determined when the property is divided. Your situation is complicated enough that you could use a lawyer. If he has more money than you do in many states he can be made to pay your legal fees.
Sign up to receive a 10-part series of useful information and legal advice about the divorce process.