Keeping this from work ppl!

I'm in my 16th week and realize it's getting harder and harder to hide my bump. But I'm going for 2 job openings at my work that if I got either they'd be huge promotions for me. So I was trying to hold off from telling my boss and anyone there until after I interviewed. Today, I finally told my boss and expressed my concerns of sharing the news due to the circumstances. A coworker of mine found out by some chance and asked other coworkers so 4 of them were talking about it, instead of just asking me. I was so mad they did that and didn't just come to me. I've done all I could to protect this from work while trying to be promoted. Now ppl know!! I expressed to her that it's only my business to share and no one else's. And if they're really concerned, come to me. 
​Am I being overly sensitive about this?