Think of it this way, your a ball python, your brain is only really capable of instinctual behaviors, most, if not all of which have to do with self preservation. Hunger and/ or thirst, mating, and fight or flight all come from that.
Now imagine, your comfortably balled up and sleeping in a nice, tight, warm space. All of a sudden, a giant thing 100 times your size, rips apart the nice hole that you found, pulls you out, and throws you in water, which is surrounded on all sides by walls, and you cannot possibly get out. How would you feel?
Remember, this is all against your will.