She's freaked out because...... The pregnancy was all in her head. Noticed how she showed no proof like a pregnancy test stick? Yeah. She had physical signs like vomiting and late period but that's about it. Pseudo pregnancy, it's a real thing.
She basically killed the STD boy over an imaginary baby.
"The Maid No Longer Desires Her Master for Only 20 Chapters"
And in case you think I'm joking, no. It stared from chapter 27 to 47, you can check it.
Home girl folded fast. Tsk tsk
I didn't count from chapter 24-25 because she still slept with Martin in both chapters and actually ran away at chapter 27