On my first flush, I felt the same way you do. I was so revolted by what was exiting me, I flushed as quickly as I could. Now, I have joined the ranks of Curezones potty fishing club.
If you eat lightly before flushing and take your Epsom Salts , you won't have much fecal material come out when you are passing the stones. A $1.00 kitchen collander is a good way to catch and examine your stones. If this is too gross, you will need a potty fishing tackle box. Items in this include rubber, plastic or latex gloves. I use the disposable kind, a strainer for scooping up suspicious looking matter, some long wooden scewers for probing and poking, and a jar or container with a tight fitting lid to save and display your prize specimens. Paper towels and disposable wipes also come in handy.
Now I am not some weird pervert to gets high on this stuff. I am a nice respectable, properly reared Southern lady. But, you need to know and understand what is coming out of you. The size, color and number of stones are all important.You need to know what is a waxy cholesterlo stone, what might be a calcified stone and what is fecal matter or undigested food.
They to get past your natural and understandable resistance to examine your BMs and use them as a way to guage your health. Besides, if you want something gross, let me tell you about passing an eighteen inch long tapeworm.......