As far as material, I suggest something non-porous like steel or titanium. Glass isn't porous but its pretty fragile. If you have a ring that closes like a segemtn, seamless or CBR, that would be less likely to fall lout compared to a nosebone or even a nose screw. Just make sure that you clean the piercing thoroughly after swimming :)
You untwist it.
A stud definitely x
You don't put a back on a regular stud in your nose! What you do is get a proper nostril screw stud for a nostril piercing and put that in instead of the ear stud you have in your nose. If the backing comes off the regular stud in your nose and it is inhailed it can go into your lungs and then you have some serious medical issues.
To out in a nose piercing, you have toClean your noseClean the stud/ringGet the stud/ring wetGet your nose wetand thenjust jam it throughBut don't get a nose stud with a ball at the end, it hurts getting in and outso if i were you, i would get what they call the cork screw.
What??
no only if your nose is really sensitive
Get something called a retainer : Its a clear nose ring . : )
One can find more information about nose stud rings on the official National Institute of Nose Health Website. A doctor can also be asked for information on the nose stud rings.
small
A clear piercing retainer
Yes
Go see your piercer for help.