I had kidney stones while I was pregnant. I had this achy pain in my back at about 20 weeks that the docs were saying were muscle aches from all the stretching going on. Finally at 30 weeks the ache turned to pain and I went to the ER. They still told me it was muscle aches because they couldn't find it on the ultrasound. It took 4 weeks for it to pass.
Make sure you drink a TON of water. I thought I was drinking alot, but in hindsight, I know I wasn't. It may have passed quicker if I had drank more. I ened up with the same terrible pain on the other side at 36 weeks along, so I went back to the ER. They admitted me for a week, pumped me full of fluids until I blew up like a balloon!
My water broke, I delivered the baby (the epidural was a dream!! First time with no pain in weeks!) and did a CAT scan. Turned out I needed surgery. The stone was too big to pass. The fluids had pushed it as far as it would go and now it was lodged. Great!
It all worked out, thankfully. But it was no picnic!
I have 2 stones right now, small, just sitting there in my kidneys. One for each side! Yay! I drink a ton of water - I try to do at least 80 ounces a day, and drink lemonade and use lemon slices in my water. Hopefully they will just stay where they are and NEVER move!
I would recommend seeing a urologist. Once you pass the stone, they can analyze it to see what you need to do to try and prevent future stones.
Good Luck! It may seem like forever, but the stone will pass and you will feel so much better!