Nowsterday means Now/at this moment/today and Yesterday combined to make Nowsterday.
It is used when you are trying to describe
something that happened around Now or Yesterday, either as an excuse or legit reason.
It can also be used to describe how fast you have/had done something.
Boss: “But I just saw you out at the mall”
Worker: “Ya, I just started feeling better, uh, nowsterday”
“I started that project like nowsterday”