Why do I keep having nightmares? please help

lately , Ive been finding it very hard to get to sleep at night and I had 3 nightmares in a row .
the first was of a scene from a really disturbing film I saw , watershipdown ( Ive had a lot about that recently )
then one about my mum dying and I woke up crying.
last night , I dreamed a deer was tied up and I ran and released it but for some reason it was very emotional , as if we where close friends ?

what does all of this mean and how can I make it stop ? please help

1) Reduce stress.
2) Increase exercise so you're tired when you go to bed.
3) Don't eat spicy foods before bedtime.

Maybe its the things that scare you? I dunno. Do u lik scary movies? Maybe you watch too much. I think it might be you give ur self scary thoughts before you go to bed. I do that. And then I'm scared in the morning. Juist be carful what your think befor bed

Definitely change your diet to include more fruits especially bananas to reduce stress, go outside more often to get some fresh air before sleeping, take walks in parks if you can. it should relax you and get rid of the nightmares. spend more time with your mom and tell her you love her, hug her, kiss her.