Poor Little Thing

Ok recently we noticed we had a mouse problem which is sad cause I have a inside cat and a outside cat yet neither catch mice how pathetic is that. Anyways I bought some mouse traps the other day now granted I didn't want to kill the fuzzy little guys because I used to own rats and love rodents but they were starting to make a mess in our bathroom chewing through anything including the wall and clothes and stuff...So as you can see they needed to go. Well just a few minutes ago I went to the bathroom as soon as I opened the door the momma mouse and baby took off scattering running right past the trap that so far they haven't tripped yet after two days. Well I had to pee so oh well ran in used the bathroom and I normally flush after I stand up and get my pants up don't know why always have. Anyways I turn around and I was half asleep its like the mouse was in the toilet but I was staring right at him and it really didn't even register until I hit the handle and he started jumping around. So now I watch this little baby get swallowed by the toilet and yet there was nothing I could do about it, and now he is gonna drown and that's a horrible death, and its not like he understood he was a baby. Now I can't sleep I feel so bad for the little guy and don't know what to do, I can't get his little face out of my head. I mean I had a choice regardless and I flushed! Is this wrong? Should I get over this or are the feelings normal or what? Anything Please! The weirdest part I still can't figure out how he got in the toilet when he won't in it when I sat down, and there's nothing near my toilet for him to have jumped out of, and I was sitting there the whole time he couldn't have got under me, and too be sure there not scuba diving through the sewage now to the house.