Hiya
I have been pregnant twice, and I am diagnosed bipolar, but wasn't diagnosed at the time. Obviously, you have come off your meds and that can be tricky in itself. If you were on sodium valproate, and still taking it, you need to urgently see a doc.
In pregnancy, the body tends to protect you and the baby, and I can only talk from my experience, it was a serene time emotionally. After the birth, I went hypomanic but that wasn't too much of a problem, so it didn't affect me too badly.
I did have some feelings of depression, but luckily had an aunt who said, try not to talk your self into it. I know that sounds wrong, we don't talk ourselves into our moods, but I was aware that I was watching for depression, so when the low hit, I was getting all wound up. So there is depression and there is fear of depression. PND is totally physical and must be treated, I know, and I am not saying that is not real, please don't misunderstand me.
One other problem is that we cannot take meds if we are breast feeding, as the baby gets a dollop of the meds too. I only breast fed for a month with each one, and whilst not diagnosed bipolar then, I did have recurrent severe depressions. When it started to hit, I stopped the breast feeding and took the AntiDs. That might be why I went a little high.
As someone else said, we are all different and there is no answer that fits all. Ask your closest friends or family to help you have insight, and trust them - even if you have no insight.
All the very best, and come back and tell us all about the baby because I know that to a mother, their baby is the greatest baby in the world. I LOVE hearing about new babies, so you won't bore me! xx