I keep having these really weird abstract dreams? And why was I hallucinating?

[Robert]

The usual explanation for dreams is, that your mind is trying to resolve something. Maybe you're trying to face some fear, or solve some problem.

Hallucinations can occur when you're not getting enough sleep. It's as if your brain isn't getting enough of whatever it does when asleep. The monotony of driving at night and the restricted vision due to the dark makes it easy for your brain to conjure up visual images.

The brain is mysterious!

 

[`Faith.]

Like those paintings you see, where there's just a mixed background of colours and nothingness and random familiar objects or people seem to appear through it and go away again, with no real logic or theme or storyline. Those were my dreams.

And just the other day, I was with a friend in their car, driving at night and I kept hallucinating. I saw several transparent moving hallucinations at different times, which all faded into nothing as we approached nearer. Such as ; the shadows of people standing in front of a road sign but no people were there; the shoulders and head of a person in a hat and cloak step onto the road and fade away; a deer run onto the road and vanish; and a person on a crucifix in the trees (this last one seemed a hallucination based around a power pole, though the others were independent) which stayed until we drove past.

Firstly, what on earth are with these dreams, please explain?
Secondly, why am I hallucinating? I haven't taken any hallucinogens to my knowledge.
And lastly, are they related?