Sometimes something just gets in the way and you can't do what you'd planned.
Maybe the wireless network goes down and you spend a while debugging it, but don't quite sort it out and need a break and get distracted by other projects, so you never post that update to your blog you'd intended to do. Just, y'know, for example.
No big deal. Things happen. S'okay.
You don't have to stress about it.
Remember the difference between "have to" and "want to". Stressing out should never be on your "have to" list. "Focusing on" or "Putting a significant amount of effort into" may be, but stressing out is rarely productive at all, let alone worthy of being on the Must Do list.
Hope you had a lovely day too and got lots done on surprise projects!