I feel pretty bad

So one of the caregivers that works here at my job is pregnant & I heard it from a cook. So I saw her in one of the halls & I told her oh hey congrats & she was like oh thanks & the other caregivers just looked at her & they  were like "oh I knew it! Why didn't you tell us"  I totally didn't know that they didn't knew. I mean since our department knew I figured they knew as well. She didn't seem upset but I can't help to feel so bad. Like they didn't know for a reason & I just spilled the beans. I apologized & just said OMG I'm so sorry I didn't know. & she was like no it's okay. Fk! Next time I'ma just keep my mouth shut. Lesson learned... I should get her a gift or something.. What do you guys think? & please those of you that are thinking negative already don't even comment! I already feel bad enough.