siatic nerve pain???

Sara
Has anyone had siatic nerve pain while pregnant? I've got a nasty pain that started in the front of my right side by my pelvis, then eventually moved to my hip and back and eventually into my butt cheek and radiated down my right leg. It is worse if o stand and walk or sit down, I can't lay on that side at all! Half way through the night the pain went into my left side as well and started to go down to the bottom of by feet. It was almost like a horrible Charlie horse that won't give up! It's since gotten better but still very tender and walking hurts. I had an untrasound today so I know baby girl is all good! Anyone else experience this??? Or have any idea how to help the pain? Heat didn't help:(