I do that all the time. The word I want is right there but I think of it hours later when I've no need of it. As for what I've done that day...well my life is pretty boring why would I remember?

No one disputes that Albert Einstein was brilliant, but he couldn't remember his address or routine things. He said; why remember what I can look up? So if it's important to you that you remember these kinds of things, what you ate, etc, write it down and tell people your mind is too full to remember unimportant things.