J.,
I know exactly what kind of pain you're talking about, and its excrutiating! I planned to continue to work until I was nearly due to have my baby, but instead I spent the last 2-1/2 months of my pregnancy either in bed or on my couch, since walking was simply out of the question, because it was so painful! My husband actually had to sleep in a separate bed, because even his turning over in bed during the night would cause me terrible pain!
What is happening is probably that your baby is positioned in such a way that he or she is laying with their weight pressing on your Sciatic Nerve, which is why the pain is so bad when you move in a certain way.
The good news is that there's nothing wrong with you, or with your baby. The bad news is that your baby isn't going to move off of that nerve until he or she is good and ready! My pain was all on my left side, for most of that time period, and it never let up. Then, one morning, I got up and the pain was completely gone. My relief lasted for only 2 days, and then I got the same terrible pain on my right side, when the baby decided to lay on that same nerve, on the other side, until I went into labor.
This may not happen to you though, if your baby decides to move and stays away from your Sciatic nerves on both sides. You may just get up one morning and the pain will be gone.....there's no way to tell.
I know that this is extremely unpleasant for you, but it will all be worth it, once you hold your baby in your arms. Also, on a lighter note, it makes a great joke for later on in their lives when they become teenagers. My son is now 28 years old, and I still tell him that he was a pain in the butt when I carried him, and that he still is! LOL
Try to hang in there....once you deliver, the pain will stop, and you will feel like your old self again, or maybe a lot sooner, if you're lucky!
I'll keep you in my prayers, and hopefully your little one will get comfortable elsewhere inside you, and stop making you feel so miserable....
D.
The pain that you're having is probably being caused by your baby being positioned in such a way that his or her weight is pressing on your sciatic nerve