Is this Dejavu or Anxiety Attack or what?

It starts with a super eerie sense of having been in the same place doing exactly the same thing same clothes people smells everything (impossible) Usually triggered by something someone says then I get kind of nauseous and hot and feel almost like I will p out. I get hot, then it pes. It comes in spurts. Like i'll have it over and over again for 4 days and then I won't experience it again for a month or so. What is this? What causes it? I have also had many experiences with dreaming things before they happen. Is this linked?