Occasionally I have moments in which I feel restless, disoriented and dread, and I'm unsure why (and if it's just me?).

I mentally compare it to being dumped in the middle of an ocean; or waking up in a ginormous modern-looking building, in some post-apocalyptic world with no answers as to how I got there, why, or how to fix the situation. Can anyone else relate to this?

It can feel very primitive, nuanced and almost chemical-like, and I'm unsure how it's specifically triggered; although I know that it almost exclusively arises in the evening. 

When it happens, mentally I start to feel as though I'm 'zooming out' of my life and psyche, very, *very* quickly, to the point it starts to feel disorienting. 

It's like my default is to be almost too closely zoomed in, and my mind starts to extrapolate outwards to the degree that everything about my life, feelings, fears and anxieties become indecipherable?

This feeling of a desperate attempt to feel safe and secure sets in, and I get extremely antsy and dread possible bad situations - having no home; getting ill; losing my friends and family. 

Although this almost never happens any other time; I can rationalise my way out of it. But specifically evening time seems to set my brain on this trajectory (I think it's something to do with if a schedule is changed, such as staying up later, eating at a different time - I feel like things are out of control, and I'm unsafe?) - is this just me?

I then start to feel very, very lonely. Again, I'm quite happy in solitude the majority of the time, and can keep to my own thoughts rather ok (I hope so at least); but I begin to feel very isolated, and very lonesome and afraid. I really crave to not be lonely in these moments? 

Not even to be actively in another's company, or comforted, but just to be back at 'neutral', if that makes sense. These feelings of hyper-vulnerability start to arise, and I don't know why (or what to do?). I just end up watching a tv show I like, or trying to distract myself some other way.

Regardless, I just felt like opening up and asking around - does this happen to you, and if so, do you know why? Are there any resources you use to help clarify / support, and is it just classic anxiety, or something else entirely?