There are also many other things that could happen when you are going to sleep, for example you can hear voice or see someone. It is called hypnagogic hallucinations.
I had one of the most incredible dreams ever last week. I was laying on the couch watching something, not feeling too great, and I fell asleep, I think. Thinking I was still awake, I began to see this city by the sea/ocean, and I remarked to myself how incredible it was that I was able to visualize this city so well because I've never hallucinated before. Then I wondered if I could manipulate it like a 3D level, and I could, so I spent some time moving my mental camera around this space, flying like superman kinda but at low speed. Then a Telsa rocketship took off from the city and crashed into the sea, but it didn't explode, it burrowed like a torpedo and turned back towards land. A woman was on a bench by the ocean and it should have hit and hurt/killed her but the rocket just disappeared. Then I realized this must be a dream and woke up. It was so bizarre, I thought I had been awake the whole time.