Hi there ,
Welcome to Just answer !
Well, what you had suffered from can be experienced by anyone ,and what happened is that you got so much engrossed and pre occupied with the thoughts of zombies , and this probably occurred due to getting influenced by such zombie movies ,and all this lead to Nightmares ( getting up late at night afer sleeping , mainly due to the vivid dreams of zombies , and then not able to go to sleep after that ) and Generalized anxiety disorder ( GAD ).
In GAD , the attention is narrowed to the object which one fears about , so much so that one starts imagining the feared objects , even when he is widely awake , and this is exactly that was happening to you , as you also started seeing zombies while watching TV.
Such kind of experience is not uncommon , and over a period of time it looses effect on the person as the memory of the feared object or situation gets weaker , and finally it dissapears and the person does not get such thoughts again .
However , the thoughts may get precipitated if you again indulge in watching zombie movies , so kindly refrain yourself from indulging in such thrills , as it effects your quality of life , as it causes anxiety and nightmares.
So, as of now , there is no need to worry and think about it , you shall just move on and do not give much attention to such thoughts .also, if at times you get too much anxious and scared then you shall ask your doctor to prescribe you 1 anti anxiety drug such as Klonopin or Buspar , and you shall get started on 1 of these for 2-3 weeks duration, and then you will be alright.
I hope this helps..
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