My mom told me those type of dream means your soul left you and is wondering around. Perhaps looking for a toilet like you said haha
I had those dreams before. It's scary and unpleasant. WHY would you leave me soul??! STAY within reach will ye?! A lot of people have died from those type of dreams, in my religion. Their soul just never came back and they stay asleep forever =[ ...
apparently some say that the soul does leave you every night and come back to you before you wake. that's why alotta older generation people tell the teens to take off their make up before they go to sleep or else their souls won't be able to recognize them. heh, i think it's just something to scare them to take off their make up before they sleep though.
i dream every night in sound and colour for a very long time now, i don't really know how real sleep feels like, i just hear the accounts of it being really relaxing and really comfortable and peaceful... i'm still waiting for that day to finally feel the same way.
right when i close my eyes i just dream on it's really bad. i had this one dream where i dreamt that i had good sleep because i wanted it so bad, i only figured out it was a dream of me getting good sleep when i woke up feeling like CRAP. yes.
another dream is when i had a dream in a dream in a dream. i so i was getting chased by one of those hoppity chinese vampires and it cornered me into the bedroom and i had to hold my breath (they can't sense humans when they hold their breaths) but the damn thing just stood there until i couldn't hold it much longer right when i breathed it took a pounce at me! before it got to me i woke up in bed frightened... then i saw the vampire again in front of my bed about to pounce at me again! then i woke up AGAIN only to realize how i was having multiple dreams in a dream.
i also dreamt that i died once, i woke up crying for that one, i saw all my friends and relatives at the cemetary where i was unable to get their attention because i was already dead. out of no where my dead grandmother taps me on the shoulder to congratulate me for being dead in perfect english -- but she doesn't know how to speak english! so i was like "WTF?" after that she took out a giant sharpie marker and started filling in the tombstone with my name and information following and i was just soooo confused to a point where i woke up because i cried too much.
those are just a few that i pulled out of my journal, keeping one also helps me refer back to incidences where i thought i had deja vus or reoccuring dreams

i honestly do not like dreaming this much and i don't know how to fix it. i want real good sleep they got to a point where i can feel pain now, and the gravity is much stronger when i free fall... so yeah, if someone is about to shank me in my dream i gotta run, because i'll feel it, but if that ever happens, i can control it

i have a skill of telling myself it's just a dream now, and to change the scene when i want to.