got off your chair, lay on the floor, didn't speak or eat or do anything, and you didn't respond to any stimuli.
This is all voluntary, not a symptom of some medical condition or something.
what would happen to you? You wouldn't just be left to stay there and die; I suppose eventually an ambulance would be called and you'd be put into psychiatric care or something. But even then you'd do nothing, and you'd have to be fed through a tube and everything done for you, despite you being fully conscious and aware of what you were doing.
the doctors would know you were consciously doing this, maybe you could even write a note saying it's a prank and they'll have to look after you until you die of old age or something.