I was wondering. I don't really know what symptoms go with bipolarity or anything like that. I just have very intense mood swings.

I will get along fine with someone. Then, I will go off on them, not really sure why though.
Then everything is fine. Then there are times where I don't speak to anyone. Its like extreme highs and lows in my mood.

And then I find myself saying horrible things about my best friends, and I am often paranoid.
And as a result of that, I often say and think bad things about myself, things that probably aren't really true.

One thing though is that I never physically harm anyone in these "episodes"

Maybe it's not really a big deal?

You really need to see a doctor, there are many different things that could cause this to mention a few, hormones, premenstrual syndrome, bi-polar, manic depression, thyroid imblance, also you need to keep your blood sugar level, on even keel by eating in regular intervals and eating food that is going to sustain you, like grains and vegatables, and stayaway from high carbs and sugars. Please start with your family doctors they should lead you in the right direction :) good luck