very curiuos

[sonam]

when you hold your pee while sleeping or lying down does you pee go upward to kidney and cause kidney infection

 

[Izthewiz]

Nope.
Been doing this for years its called bladder training.
Your bladder can hold a lot more then you think.

 

[bin_tenn]

I agree with @Izthewiz . If your body actually needed to go, it would wake you up. Instead, it just holds until it needs to go, or until you wake up, and all is well.