Second time around with a toddler, help!!

Sade

Hey I’m in my first trimester (9 weeks to be exact) and my 3 yr old son keeps acting out. He started off sweet in the beginning of my pregnancy and now he just yells and whines all the time. FYI, He doesnt know im pregnant yet. What did you guys do to deal with this? Does it stop? Is the intensity of his behavior contingent on how many babies I’m carrying, or the sex of the baby? I’m just so confused because around 6 weeks and before he was soooo sweet. Or is this just something that happens with toddlers at this age? Lmfl please help me out bc I’m doing everything I can do.