I too have been feeling the same way, though only extremely recently. I've always suffered from basic seasonal depression. Normally, I just become tired and oversleep, and also lose interest in most things. I've never been a very emotional person and rarely cry.
I started college last year, and again suffered my general seasonal depression symptoms. However, recently diagnosed with ADD, and prescribed adderall. My doctor said it might address my depression issues too, because it helps keep me alert and awake. I've been taking it for a few months now, with no issues. It's now around the peak time for my winter depression to kick in, and I've only been feeling slightly tired, much less so than other winters.
Recently however, my mom moved out of my hometown. While I'm at school, it doesn't bother me. But there are often little reminders that I don't really have a place to call home. I now stay primarily at my dad's, a place I used to "just visit". I now find myself struggling to decide whether his house is my home, or my mom's new place is my home. A few nights ago, I went to my hometown for a small concert, and that's when things snapped. I had arrived there in a very out-of-the-ordinary context, and I started to feel very uncomfortable and alone in the one place I thought I could always feel safe. I broke down and sobbed, and eventually had to call a friend. I started to feel better, but then we stopped talking for a bit and I started sobbing again. After, I met of with some friends for the show, things were fine, and the next day I went back to my college town for work, and was also fine.
Randomly though, in the middle of class yesterday, I started having this strong feeling everyone's been talking about. I started feeling queasy - not nauseous - like I was extremely uncomfortable, or like I was in a new situation and really nervous. What made it worse was that there was no reason for it. I knew where I was, and everything was as it normally is, but I felt like I would if I were somewhere new and different. I made it back to my dorm, and broke down again. (Again this is something I NEVER do.) In the moments where I felt detached from reality, I felt like it was never going to end, and I was afraid I was never going to feel connected and comfortable with my surroundings. I was also afraid this was going to progress to make me feel like I couldn't trust anyone. I decided I should let people know before that did happen.
I find I feel better when I'm around people I know. Even though my college is pretty big, as are my classes, I felt alright in my classes today. But after, I went back to my dorm, made two phone calls, and felt fine. But I also felt like I was going to lose my grip, and start feeling disconnected again. I took a nap, and woke up feeling disconnected.
Another thing that I've noticed is that when I'm in my dorm, I don't want to leave. It's like I'm afraid that wherever I go, I'm going to start feeling this feeling again and not know what to do. But even so, I still get the feelings in my dorm room, so really there's no reason for me to feel like leaving is going to be especially difficult. It's like a fear or anxiety based on nothing.
In these moments, like I said, I feel completely disconnected from the world and myself. I'm doing things and even saying things like I normally do, but it's like it's out of habit. I'll maintain my normal sense of humor but it's like it's not me. And I also feel like I'm just completely alone, like even if I find someone I know and trust, they won't be there for me or something. Normally, I've been a very independent, introverted person who enjoys my time alone. Now I feel like I'm desperately trying to stay in the company of people I trust to feel better.