How to not say anything about my pregnancy?

No I’m not trying to be sneaky. I definitely don’t want to say anything to anyone until I made it in the clear as I had a chemical. I want to wait and surprise my SO until I take a couple betas as I don’t want to get his hopes up. SO has no kids and didn’t believe me about my chemical so I have my reasons. It’s just sooo much harder than I thought cz I am having bad headaches everyday. SO has made comments before like “I think your pregnant” bt that’s routine bt now I feel suspicious. It shocked me as he’s never had any scares or nothing. How do other women just go on acting normal? I feel like it’s written on my forehead. Luckily I quit drinking two months ago so I don’t have to give excuses for that stuff.