I can so relate, I did something similar last night I was working on a paper pieced block -I had precut squares for the different parts, then ran short,cut another one, then found the one that had somehow jumped off my sewing table and committed hari kari. LOL. I just call them Sr. brain cramps, and chalk it up to getting older, being interrupted too many times in a day, and not because of kids either. Oh well, onward and upward - the quilts await.