This was cool idea.
I feel the heart beat effect could be dialed back a bit. Having it get louder and faster the closer it gets creates some really good suspense, but having it going non-stop does make it slightly less impactful. Probably shorten the radius between the player and the monster to where the player starts hearing the heartbeat.
The controls of the gravity fields that either push or pull are very unique and are used quire well. Nice job.