Dreams

hi , just curious if a psychologist or someone knew the answer to this lol .

So basically I only get nightmares if I sleep on my right side when I’m in my apartment . When I’m at my parents I can sleep on any side and be fine. It feels more comfortable to sleep on my right side tbh. This morning I woke up at 7am because in my dream I was a victim of school shooting lol, and I graduated like 6 years ago . The crazy part of the dream was like the shooter was one person, and then it somehow changed to another person, and then it changed to another person . And then like one of the teachers literally grabbed the gun, and the person had a knife so it was like I HAD to be harmed in the dream. So I was just wondering why that happens? Thank you.

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