Oh man so much... let's begin

Both you and a mouse can experience pain

Prove it. Prove my perception and the mouses perception of pain are the same. Does a trout experience pain? How about a worm? How about a bacteria, do you weep when you take antibiotics? When you kill a fly?

Killing a mouse in a way that does not cause it pain is more humane because experiencing uncontrollable pain is not pleasant.

Pleasant is a human construct, you are anthropomorphizing, you are projecting human perceptions onto a mouse. You need to prove the mouse can perceive things the way a human does.. good luck.

Is being eaten alive more humane? So you think trapping it, (whereby if we apply human emotions it would be greatly distressed), and then releasing it far away from it's home (still sticking with human emotions) to a field where it will likely be eaten alive by a bird or cat is somehow more humane than quickly snapping it's neck?

I'd rather not experience pain, and I'd imagine the mouse probably feels the same way

I imagine all sorts of things, it doesn't make them true. You are telling me you know how a mouse feels?!! Are you a mutant? You have super powers?

If you try to argue that than you're just insane.

You are the one who thinks they have super powers.