Does the day I was served with an eviction notice count toward my deadline?

No, and this is a common miscount. The papers landing in your hands, or getting posted on your door, doesn't start the clock that same day. Day one is the day after.

It's a small distinction that matters more than it seems, especially on a deadline already measured in single digits. Getting this wrong in either direction, counting too early or assuming you have a day less than you do, changes how much runway you actually think you have.