Another kidney stone sufferer here. I have had two, and they were both quite different. The first one I had 10 years ago was on my right side. I had noticed for several days that everytime I went to the bathroom, I immediately felt like I had to go again. I had wondered if I had a bladder or kidney infection, but since I had never had one before, I didn't know what it was supposed to feel like. After about 3 days of this, I started having a niggling pain on my lower right side that within a 1/2 hour became excruciating. My secretary had to drive me to the ER where they would not give me pain medication since they didn't know what was wrong. A urine test showed blood in my urine and they also did some sort of dye test that showed the blockage. Thank goodness I passed it in about 1 hour and I bounced right back.
The second one was about 5 years. No warning symptoms at all. I woke up at 2 in the morning in lots of pain on my lower left side, laid there for about 10 minutes with the pain getting worse, and I finally decided to drive myself to the ER. (Dumb, dumb move that I will never do again!) When I got to the ER, I knew it was definitely a kidney stone and I was demanding drugs. Let's put it this way, the lady who checked in next to me was in labor was in lots better shape than I was! They gave me one type of drug and told me that if they gave me something stronger I wouldn't be able to drive myself home. Within a 1/2 hour they were doing the dye test and shooting me up with morphine. Yep, this time a blockage on the left side. After I threw up about 5 times I started feeling better and they sent me home. For the next 10 days, I had attacks on and off. Sometimes in my lower front, sometimes in my back. (The back ones felt like someone was sticking my with a knife.) I finally passed it.
So, I guess the moral of this story is that they can act differently even for the same person. If the pain gets to be too much, please get someone to take you to the ER. I was unable to see the blood in my urine both times, but it did show up in the tests.