The game isn't bad at all; it really captures the feeling of being trapped and helpless, and how awful it is not having legs.
Something I recommend is adding death cinematics, whether it's a broken neck, being eaten, or torn apart by others, because that adds so much to horror games <3
Another thing I recommend is showing how much it's hard for the character to breathe, either by setting a time limit on how long they can stay out of the water, or by having them find puddles to get wet and keep breathing, or simply by blurring the edges of the water.
That said, these are just suggestions; what you're already doing is fantastic <3