[Skyline]

Hi, so I'm going to say this first: I have never been clinically diagnosed with depression, so I'm not really sure what it feels like exactly, which is why this is a bit confusing for me...

For the past two weeks or so I've been having on-and-off days of feeling really, really... Ugh, I dunno how to even describe it. It's kind of like a mix of anger, giving-in, solitude, sadness, desperation... but more intense. I'll feel totally fine and perky one moment, and then the next I'm in this lost zomby-like state...
I'm a very spiritual and philosophical person, so I'll often have deep thoughts about life, existence, death, and usually this will just lead me downwards into a pit of confusion which will causes me stress, anger, frustration, and just feeling insignificant and worthless.
This morning, I was feeling exactly like this, and I often got thoughts like "hey, but the good thing is that if things get too shitty, I can kill myself, and then it'll all be over" although I don't seriously consider death as an option of stopping all this. However, it is in the back of my mind, but it's more reassuring than anything else, to know that if things get too bad I have that option. So yeah.
But it was weird, because if my friends said or did something funny, I'd be my normal self and laugh and joke, and then a few seconds later when I was left with my thoughts, I was in that "dark" state again.
A couple of my friends came up to me at one point, and asked how I was feeling, because I looked quite miserable and lifeless which was disturbing to see because I'm usually quite a perky, happy-go-lucky person. I told them that no, I didn't feel good, that I just felt like sleeping and being by myself, that it felt like something in my life was wrong but I didn't know what, but that it would pass. Which was precisely what it felt like.
Anyway, right now I'm feeling absolutely fine, which is good. I was just wondering what you guys thought of this... like if it was the begining of bipolar depression or something... I dunno. If it is, I obviously want to avoid it.

Please tell me what you think! any comment will be appreciated!