It is natural to see dreams. Most of the time the content of the dream is what we see and experience though out the day. That can in-fact give you a déjà vu effect (As if it has happened earlier) or my dream has come true. The sexual dream about a close relative is also natural. But if you want you can see a psychologist if it is affecting. I would not call it fear of sleep rather it is anxiety about dreams.
Next Steps
See a psychologist/ psychitrist online offline
Health Tips
Dreams are not truth. If all dreams came true you would have dreamt of become rich etc. It is absolutely normal unless the frequency is very high.