S.H.
Yes as the other's said, speak to your Doctor about this. See what the recommendations are and the "solutions."
Also, you said you really want 1 more baby. That makes 4 kids. Have you talked about it with Hubby? Is he in agreement? I'm sure he must be concerned about your health too? What does he think? He will be a part of this too, and caring about you and caring for you... and the new baby if so. I'm sure he must have thoughts on it too.
But if you think you can handle it all, and Hubby too, and have medical help for your ailments & if Doctor can offer positive advice....then that would be a great thing!
Next, you seem torn on being able to nurse or not. It's hard to predict what will happen... but you need to be prepared to do what is best for the BABY. No matter what. THAT is the primary priority. A baby must feed no matter what or how.
All the best,
Susan