I have hardly any self confidence, in my school I feel like a joke and I feel like im in a tantrum sprial into melancoly. Yep my life is great.
I used to be the same way, that poor kid in corner that can't hold a conversation for more than five seconds. Learn to start conversations, and then to keep them rolling.
Its hard when you didn't have any social life during middle school. Middle school was hell for me.
You sound just like did. Start by looking people in the eyes every now and then and keep your back straight while walking (I used to walk all huddled up), you'll "feel" much more confident this way. Then, after you've got that awesome feeling of accomplishment, try to talk to random people. Starting a conversation is the hard part, but when you've got it going, it gets easier. People won't hurt for saying "hello" or "good morning", if you know that, you're golden. Find a random person you want to talk to, and try to think of something to say, something you two have in common and can discuss. If you're on a bus, it can be "Where do you get off?" you see someone reading a book you read try and start something conversation with that, etc. People love to talk, and they love people who listen, so you're fine as long as you keep the other person talking. Ask open ended questions, words like why or how are great, because they ask for an explanation. Listen to the other person, look at him/her and keep asking. You'll notice you have no trouble speaking to the person, as if you've known each other forever.
Don't do it all at once though, start by feeling confident, and then start speaking to people.