I have never heard of this "trance" state. Could it be similar or identical to what most call the vibration state? Anyways, you probably picked up on some energies in the area, or maybe you picked up on spirit energy. Also, when in a meditative state you are open to energies like that, including spirits. From what you said about the fear, i would guess that you indeed have a spirit.
To really prove this, i would have to be there unfortunately.