Is there something wrong with me?

My days are usually just me being really paranoid. Maybe about once a week a have a day where I'm just sad and don't want to get up or watch tv and have no appetite at all. And usually I have one day where I'm really mad and all I want to do is sleep. Even when I think I feel fine my friends usually tell me I seem like I'm sad. I'm overly sensitive, but if I read a story about Columbine or a wounded dog I will hardly feel sad, but I cried at the episode of Family Guy where Brian talks about killing himself. I'm about to cry just writing about it. It's like I have a "trigger-word" for crying. I'm usually only happy around my friends, but it's genuine happiness. They're the ones I feel the most paranoid about, though. The slightest things they do make me really cynical. I get so anxious from the paranoia that it feels like I'm shaking but it's just on the inside. Sometimes I just start crying because my mind's set on default that if I don't have anything to think about I think about myself. I just feel like a failure and the only reason I'm only still here is because I have people that care about me and need me, and I feel so ungrateful that it hardly helps at all. When I feel sad I don't even want to talk to anyone. When I was younger I didn't have some cliche "huge scarring of my life". The only think that could even hardly be clified as that is when I was younger I only had one friend but then my parents divorced and I didn't live by her anymore(I still lived in the same school district, though), and then I starting getting on the internet a lot. My parents got back together a few times after that. I now live in a blended family, and they're tolerable but sometimes they push me to my boiling point. I still talk to my dad, he lives with his girlfriend and her kids. They're all tolerable most of the time. I'll be honest, I'm only fourteen, but I've been suicidal since I was 9 or 10. I attempted once when I was 10, but it was really pathetic and I've never told my mom. Sometimes I just get so mad I wanna tell her and make her feel guilty but I know I'll regret it. I don't self-harm, I've only cut once with a box cutter when I was 10. It was on my arm my mom never seen it because I had long sleeves and jackets. It was like a tic-tac-toe board but I only have one scar from it. My mom found a paper once when I was 9 and it was ways I could kill myself. I was just angry I was just taking out frustration but it eventually became a joke. I vividly remember putting down "cut off my arm" on it. I think my mom's suppressed that memory, though. She's never brought it up since. My parents divorced when I was 7, but it was probably for the best and I'm really not bitter about it. Right now I'm in one on one of my sad days but it started happy, then paranoid, then angry, then I was alright, now I'm just sad. I truly think my life isn't that bad, but I just can't be happy. Sorry it's so long..is there something wrong with me?