I had one in '97 and admitted myself into the ER, $7K later they told me I had a stone and to go home and pass it.
In '99 I got another and after passing it myself without a visit to the ER I went to a Urologist (He used to own a GT2 and sold it to the owner of Tire Rack and bought a 360 Mondial, I liked this guy) and he ran tests on my stone, no conclusive evidence of anything wrong with my diet or me.
I was told I was dehydrating myself too much, I worked outside a lot back then when my Surveying company was young.
How to minimize the pain? Drink lots of water tons of it. Like over a gallon a day, and set your alarm to get up in the middle of the night and drink lots then too, bever let your bladder run dry.
The first stone I passed was painless the second almost put me on the floor passed out.
I suggest you pee while sitting down from here on out. They shoulf have given you a screen to pee in anyway yo catch the stone.
I have a woman friend who has been through the stone thing too and she would prefer to give birth again over it any day.
BTW- Pain killers really do not do anything, they take the edge off a little but, honestly the best thing is to keep you bladder full, the pain you feel is the stone hitting a wall when you bladder is relatively empty.
Good luck and hang in there.