Nightmares are superficial thoughts. It means your have had a difficult or anxious day. you ate afraid or anxious about something, that is occupying your thoughts throughout the day. Or you could be anxious about something in the near future that is very important that you feel is life changing event. Try relaxation techniques, breathing exercises. if these don't help, consult a psychiatrist.

Hi there, I m Dr Diwakar here. I have read your complains and I think u r suffering from a condition called parasomnia. since u did not mention if u r on any medication or drug so I take dat as a no. for your problem the solution is quiet easy actually and it requires consultation and prescription from a psychiatrist. this condition treatable using medication. so feel free to consult and feel better.