Why am I having such morbid dreams?

I think there is something wrong with me. 

I keep having vivid dreams about people dying. I had a dream a couple of nights ago about the genocide of the Rohingya people, that they were massacred and buried in a field. 

And then I had a dream about a murder crime case where the man murdered his wife drowning her in the bathroom and was about to murder his sons. 

I have not been watching news or crime dramas for the longest time but why am I having such vivid but morbid dreams?

Oh dear. 

pearlie