Spot the Mistake

Hello! This is my first time posting here. I thought I'd let you know what I've done so far. I'm knitting the vest version of Butterfly, using Kidsilk Haze in "Trance". This isn't really a color that I'd normally choose for myself, but I had it in my stash, and I actually really like it. I've knitted the frill for the back (this was a painful process - I had to lock myself in a room with no distraction to get it done), and I've picked up stitches to start knitting the body for the back. But, can you see what's wrong here?

That's right, I picked up the stitches for the body from the wrong side of the frill. It took me forever to notice that I'd done this, too (in fact, it took taking a photo of it, where I couldn't work out which side should be 'up'). I couldn't really believe I'd done it.

Since making this mistake, I've slowly ripped back (I'll never make this mistake again - undoing Kidsilk Haze is a special kind of punishment), and I've picked up (on the right side this time), and have got back to where I was before. Much better.