How to take care of wild mouse?

My cat wanted in at 1am, seen he had a tail hanging from his mouth, held him upside down till he dropped the mouse and put the cat in the spare room, the mouse is so small like an inch, I picked it up using a cloth, and now have it in a small iphone 4 box inside a bigger box, it had a tiny spot of blood on the cloth, I've put down paper towels, bottle lid with water and some cheese slice, I'll do alot more for it once I've had a sleep, the box is inside my cupboard like 4 feet away I can hear it walking and sqeaking a little, left it there for a couple hours and looked inside its done a few poo's, Will it chew through the box by the time I've woken? What else do you think I should do? I'm 22/male, this is too sad for me I have a massive heart

The cat bit it right? It will probably die from infection. Cat's mouths are loaded with bacteria and can wreck even a human's immune system. Imagine what it does to a tiny mouse!

You are a good person, that is clear, but I think you are just prolonging the inevitable. If I were you I would take the mouse to a "safe" location, away from your cat, release it and hope it pulls through. If nature wants it let it have it, if not well then…

I hate to sound heartless, but this is just another part of life. Cats do this. Next time I wouldn't intervene. My cats sometimes catch mice. I never remove them from my cat's grasp unless they JUST spotted them and have yet the pounce, then I distract my cat and scare off the rodent. If I'm too late I just look away and let life take it's course.

I'm a rodent lover, cat lover, all around animal lover, but sometimes you just gotta disconnect.