my strange dream

i had a strange dream last nite and i cant get it out of my mind and i dont no wot it means i dreamt i was in my bedroom looking out the window and someone dug up a grave in my back garden and when i looked in the grave from my window there was a girl in the coffin and as i looked at her her eyes opened and she smiled at me i told everyone because it scared me but no one would believe me so i went into the lounge and looked out of the patio doors she got out of the grave and started towards the house to the patio doors where i was stood the doors were locked so i knew she couldnt get me and i went upstairs where i thought i was safe and as i went into my bedroom and she somehow managed to go through the window and turn into this mass on my windowsill with a head face and hair i went out of the room to get away from her but she turned back into a human form and came after me trying to strangle me my partner managed to get her off me long enough for me to kill her then i woke up what does this mean?