RUN!
You end up staying still, not moving an inch as if you were convinced the Jurassic Park "It can't see us if we don't move." mantra would work. After a while, the feeling of being watched seems to have subsided, almost like that thing had left you alone; thank you, Spielberg! You feel at ease and remain still for a moment longer, wondering if it had left you for good. Maybe it would be best to hide now?