If I found myself with a weapon in my hand and could not remember exactly how when and why I got there. I would secure all of my weapons, somewhere I could not unintenionally get one and hurt someone with out knowing what the hell was going on. I am not trying to be funny or crass. It sounds like you have ptsd and you need to seek help A.S.A.P.
I have no idea what happened to put you on edge but do you want to shoot a family member on accident because you had a need to have weapons on hand to ward off imaginary attackers. Unless I am missing something you are MUCH more likely to have such an accident than to realistically need to come out of bed with a shotgun in self defense. What the hell would you do if you shot someone and could not remember the exact timeline and reasoning for the actions?
put weapons somewhere secure and out of reach.
seek counseling and or medications to calm you down and find the source of your unrest.
avoid lines of work that expose you to events that unbalance you.
I consider myself a very wary fella I carry backups in every concievable location and I have continecy plans for every situation imaginable. That said what you are describing goes way beyond normal safety concerns and actions and needs to be addressed.