So rude!

Am i out of line for being upset by this? I went over to my friend's house and someone who is friend's with my aunt was there. They were all drinking and smoking and i didnt want to have any part of it especially being pregnant. This was a few weeks ago and i was only about 5 weeks along & i just found out. When they asked I simply told them that i was pregnant and i didnt want to join in. I knew this woman was friends with my aunt so i told her, "Please keep this a secret because I want to be able to share the good news with my family first." She said she wouldnt say anything. I now found out that she told a ton of people in my family and it took away from the surprise completely. Im so disappointed. I know all she wanted was someone else to talk about .. but it hurts because i wanted to be the one to tell them and now when i did, i didnt even get a congrats.. i got a "well i already knew" should i confront her or let it go?