You felt the fear because your brain was trying to warn you that you were pushing your body dangerously beyond its limits. Your mind created the Indian to go with the fear, that is why you felt the fear first. It's an instinct we have that sometimes keeps us alive, intuition sometimes works like that.
Suzie Q, what you had sounds like a hypnopompic episode and it's pretty common. It's normal to enter sleep paralysis as part of REM sleep. When we awake and become aware while still in sleep paralysis, vivid hallucinations and fear are experienced. Often the hallucinations are carried over from a dream the sleeper was having as part of REM sleep. Google hypnopompic.