FB FRIEND ANNOUNCED MY PREGNANCY BEFORE I GOT TO

Would you be upset if someone ELSE blasted all over FB announcing you are pregnant and tagging you?  I didn't even get to announce it yet, or have even had the chance to tell my family yet.  My son doesn't even know yet.  I wanted to do something special when I told, but now everyone freaking knows bc of big mouth.  It was my SO's ex-girlfriends' sister.  They all still get along, and she even said she was going to be an aunt again-tagged me and my SO.  Am I overreacting here?  😕