The Missing 'to-do'

I have spent my day getting things done and going about my usual routine, and yet, something seems wrong. I have checked my 'to-do' list twice and everything that can be done this evening is finished. I have practiced all afternoon, I do not have any homework, what could be left? I feel like something needs done, but I cannot put my finger on it. Something about my day feels incomplete. I think back and I have completed every part of my routine, I left nothing out. This inexplicable feeling is not a great one to have. Hopefully I figure it out and do whatever needs done...