My coworker told my boss I'm pregnant!

I am 7 weeks pregnant and did not want the news to get out until 12 weeks. I ended up very sick last week and told a coworker I was pregnant, only because she thought I had the flu and wanted me to go home. I explained to her it was still very early and I didn't want anyone else to know.

I found out she told my BOSS a few days later when I was not present!! I was planning on talking with him first and now I found out he went to our HR lady (who knows I am pregnant because of doctors appts) to ask and verify that I was pregnant, while that coworker was standing right next to him!

I'm very upset and I don't want to face either of them. I'm afraid of the reaction I will get from my boss since I wasn't the one to sit down and have a face to face with him. Should I just forget it and not talk to him since he already knows? Or ask to talk to him and explain the situation?