Sometimes you have those days in which all you can do is put one foot in front of the other.
Create a list and take one thing at a time, if possible. If you have to juggle keep the list where you can see it so balls don't get dropped.
However, if something gets dropped you have to realize that, in most cases, it won't kill you.
The key issue is understanding that as long as you keep moving the clock will keep ticking and that, sooner or later, the end of the day will come.