Ok so I'll start off my saying that I'm 19, and my urine is very clear. I drink lots of water throughout the day. I have also been to the doctor for a urine test, and nothing was found. Sometimes when I urine, I will pass these small white particles, the size of a grain of sand. I picked one up once to see if it was solid, and when I started rubbing it, it dissolved into a bunch of tiny pieces on my finger. I can feel when they pass through as well, it sting just a tiny bit. Also, about three weeks ago I passed a kidney stone as well out of the blue. This has been happening on and off for a few years now and I've tried not to worry about it because it doesn't really happen that often. Could this be due to something I am eating/drinking? Thanks