D.K.
I had three back surgeries to attempt to fix a couple of herniated discs at L5-S1 and L4-L5 between my first and second children. My back was injured at work in the military and they dithered around with getting me an MRI for 3 years! So by the time they did an MRI the SI nerve in my left leg was "dying". They tried taking the pressure off but the nerve never recovered (they can't regenerate). Now the damage done to the nerve and the disc that is still herniated cause muscle spasms in my back if I'm not careful how I use it. During my pregnancy with my second child I had a spasm that lasted for my entire second trimester so I was on bedrest and Percocet for months along with crutches (for when I needed to go to the doctor or physical therapy). I was allowed to crawl around my house to try to keep up with it as much as I could because my condition wasn't a danger to the pregnancy. I was a pretty pathetic sight! lol! Finally the spasm released and I was able to slowly get back to moving around. Muscle spasms are excruciating (it's basically a charlie horse, but mine involve all of the muscles of my back and last for months with no relief). I also had back labor because I have a tilted uterus and it SUCKED if I remember it right! But it was over long ago and I can barely remember it. I only really remember holding my son for the first time, how proud my husband was of me and the huge smile on my older son's face when he saw his little brother.
My best advice is to just roll with the punches. Explain the situation to your doctor and your concerns exactly like you described it on here and get his/her advice on what you can do. Maybe ask if there is any kind of specialist that is available to deal with pregnancies in orthopedically disabled women and get a consult. Follow the advice you're given, don't hold back when describing your pain and most of all, just take care of yourself the best you can. If that means staying in bed for a few days here and there to rest and recover then so be it.
And remember, pregnancy is a temporary state of affairs. It'll be over soon enough and then you will have a beautiful gift of a child to make it all worth it. It doesn't matter HOW the baby is born. Having a C-section won't make you a bad mom. All that matters is that you keep yourself and baby healthy. Concentrate on that and let the dreams of a perfect pregnancy and delivery go.
Best of luck to you and congratulations on your first child!