Since our brains actually believe what is taking place in a dream to be reality at the time, it is no wonder that on occasions that our sense of reality gets lost form time to time.
And when you could not correspond with an outside referance, your mom in this case, it can become more vague. Along with that it was a trivial event. For if you were flying out a window there would not be much question.
Then the more you think about the situation the more factual it a may become.
No wonder none of us no wether we are in a dream or in reality.