Need help Coping w/major stress

My name is Tiffany and I am 28 weeks pregnant. I also have a 4 year old son whom I have raised from birth and have full custody of. I'm currently awaiting a court date in May to determine whether or not I will continue to be the full time caretaker of my son. His father has decided to fight me for full custody of our son. I am emotionally a wreck because I love my son more than anything in this world and I have all the reason to have custody of him as his father does. So, this could go either way. I'm aware that the stress is taking a toll on my unborn daughter and I'm worried now that this could potentially cause her to be premature or even weigh less than she should. I'm in need of any advice from moms out there who could relate to my circumstances or who know of ways to cope with major life stressors while pregnant. I'm constantly anxious about both my court date and the effects my stress is having on my unborn daughter. Please help me!