chemical reaction

She was sitting just across the room,
focusing on her measurements.
Her hair was tied up in a messy bun,
enough to get it out of her face.
Frowning and biting the inside of her mouth,
her hands moving slowly, without trembling.
But then I tripped, fell down.
She got startled by the noise,
her hands out of control.
So she accidentally poured too much.
I heard I bubbly sound.
I heard her call my name and swear.
And then the room was foggy.
She coughed and shouted,
but I wasn't listening.
Something had come out of the fog.