Why do I keep having nightmares

Do you eat before going to bed?

Do you sleep to warm?

Have you pissed off your wife recently?

My 20yo son has this too, it sounds horrible.

Stop watching Liverpool football matches on TV !

Too much cheese

It could be stress or something you preoccupy your mind with. Or it might be your diet.

Somwthing is bothering you

Sleep paralysis?

Bad energy.
Repressed memories, and past trauma.
Moon phases, spirits.
It can be a number of things.