You guys here are pretty knowledgeable and crafty so I thought I might ask you a fabric/cloth-related question!

I bought some really light pink ballerina flats from Urban a while ago. They appear to be made out of some sort of fake suede that easily picks up dirt and collect water "stains." After a few wears they looked pretty dirty so without thinking anything of it I stuck them in the washing machine. When they were done, one shoe came out normal and the other shoe came out way darker. I was like, what and put them through a couple of more washes thinking maybe something got washed from one shoe but not the other but it seems like the other shoe is permanently stuck a darker color somehow and it's really disappointing. Does anyone have any ideas on what happened or how I can make the shoes the same color again? Should I let them sit in some bleach for a while or something?