I'll add my pain experience to the pile.
I had the pain on and off for a couple of weeks, along with a feeling of general malaise and nausea. My dr. kept telling me it was heartburn, because my pain was centered right at my sternum. She prescribed prescription heartburn meds. When that didn't work, she sent me to the gastroenterologist for gallstones (it was finally that bloodwork that showed the elevated LFTs).
I had a giant bruise right over my liver on the right side, where blood vessels had started to burst because of the pressure of my live swelling. The dr. dismissed it. (My current peri always refers to me as "the bruise patient" with her students, because apparently that is so rare and serious).
I also had pale, clay colored stools and very dark urine. When I complained that I just didn't feel well and wasn't feeling the baby much, the dr. sent me to L&D for monitoring. The nurse gasped when she saw my urine sample. She thought I had a kidney infection. I told the dr. my back hurt, because by that time it had started radiating around to my back, but she said the pain wasn't from my kidneys because it was too high up (duh, it was right over my liver!) She never even ran bloodwork, just checked the baby and sent me home.
The two days before my son was delivered, the pain was so intense that I literally could not sit down, unless it was bolt upright in a chair; any slumping or leaning took my breath away. I couldn't lie down, and I think I slept all of one hour the entire time. On the way to the ER, I cried every time we went over a bump in the road. It was the most intense pain I've ever felt, with the possible exception of having an ovarian cyst burst (although that is acute and resolves fairly quickly). I was happy to get the mag because it actually helped relieve some of the pain (along with the pain killer they gave me).
By the time I delivered, my platelets were down to about 30,000 and my liver was near rupture. I am incredibly lucky that there doesn't seem to be any permanent damage.
They say you forget pain (otherwise, why would women have more than one child?) but I have not and will never forget that HELLP liver pain!