Dear higirl:
I am sorry that your having constipation. I wouldn't think that your constipation is due to "nerve" problems. Other that the constipation you do not indicate that a neurological cause may be probable, i.e. symptoms. I might check out the lower back problems, there are times that delivery can induce some lower lumbar problems. However, this usually does not cause constipation problems. What does your GI specialist think about your GI problems? I think I would pursue this area as the source of the problem. You are doing the correct thinkgs in trying to increase your fiber.
Sincerely,
CCF Neuro MD