Here is what I want you try at first. Have you ever tried meditation? I think this might help all those feelings you have been experiencing.

Get into a comfortable position like a comfortable chair or crossed legged on the ground. You want to be totally relaxed while staying awake. Close your eyes, then completely clear your mind. Any thoughts you might have just let them float away, that means if you hear any inner voice just genitally make it quieter. Keep doing this for around 30 minutes if you have time, it is basic meditation but its effective. Maybe try to do it before you go to sleep, sort through your feelings. Keep practicing this each time before you go to bed to calm yourself.

So I suggest trying the above and see what kind of results you get. I completely understand the feeling. I use to have a lot of night terrors where I would wake up and be in complete fear like I was sick with the emotion fear and was having an emotional vomit of it. Not saying what you are experiencing is a night terror, just saying I have experienced unpleasant things while sleeping as well. So hope it goes well for you.