Exhausted at 6 weeks!

I told one of my coworkers I was pregnant and I was only 6 weeks along and I'm exhausted all the time and she looked my stomach, then at me and scoffed, "You're exchausted?! Seriously?" And then left.

I wanted to throat punch her so bad. Do I have to be showing to be tired? To have any symptoms?

Ugh. Needed to vent. It's my second child and exhausted and morning sickness are kicking in high gear. And my mood swings!