I was walking in the forest to kill this strange thing. I was alone versus her, it was terrifying because I didn't know where she was whereas she, she was seeing me.
I was walking yet and yet when all of a sudden ( suddenly est correct mais "all of sudden" est préférable ) I heard cracking wood. I began to stress and be frightened. I watched around me but nothing was here when suddenly something jumped on me.
It was her ! Her* teeth was neon blue.
I screamed with fear and anger (pas besoin de mettre "the" ) but I managed to catch my knife and I killed this strange creature.
She was black, a very dark black, and her blood was as her teeth. She was terrible to see.
But I killed her. The pride in me, I decided to leave but strangely I felt like heavy. I closed my eyes and I [...]
Je me suis permis d'ajouter quelques mots (en italique) pour renforcer un peu ce que tu dis :)
His : adjectif possessif utilisé si le possesseur est masculin.
* Her : adjectif possessif utilisé si le possesseur est féminin.