throwing out a agreement

[PeaceNJoy]

Im a young mother my son is 3 years old. My ex and i have never been married. My ex has a been mentally physically abuisve to me for over 5 years. My son was born at 25 weeks I had to drop out of high school to care for his needs. During that time my ex and his mother filed for custody we've been in and out of cort for the past three years. This last time me and my ex were living together I was corherced into making a agreement that is not in my favor.

My son dad with held my son for a period of two months i didnt know the whereabouts of my son at all. Since then my son's dad was arrested only for a short peiod of time I tried to go get my son from his mother she denied me. We recently went to court and now they have entered that agreement from Nov 8 2011 . But we are in feb. I've been tooken adavantage of my ex allows his mother to execrsize his parenting time. But the agreement made allows that. I'm in fear that my agreement  has hurt my chances of ever obtaing physical sole custody. My ex never was orderd to pay child support dosent keep a steady job. Please tell me are my chances good to ever get  physical sole custody