Yestoday
When it's midnight and you are talking about the day you just spent, and get it confused with the day before because it's past midnight and your mind is technically set on the next day, though you didn't sleep yet.
Roxanne @ Midnight: "I can't believe that I travelled so much yestoday. I'm so tired."
Yestoday
The term “Yestoday” is defined as today and yesterday combined. It shows two specific time periods and events that can happen during both times or having two days combined into one term.
I've Been working on my homework since yestoday.