How early does morning sickness start?

Nikki • Married since Aug 2012. 1 Daughter born in Aug 2016. 1 son born in Oct 2017.

This morning I woke up starving, but when I actually was sitting in front of my food, I felt queasy. It was all I could do to choke it down. Husband and I have been TTC #1 for 4 months now. I want to be pregnant so bad. But I don't want to psych myself out. When I do that, I get bad depression when my period comes. So I made a rule that I can't take a pregnancy test until the day before or day of my period, so as not to get my hopes up. I'm now 10 days away from my period (it comes a few days late more often than not), and today has me feeling excited that I might be pregnant.

So my question is: how early in a pregnancy does morning sickness start?