How do i build more self confidence?

I keep everything bottled in. I don't know how to let it out
and when I do, I blow up completley and have like a panic attack.
I usually don't get stuff off my chest until things get really bad.
How do I change that =l

just write it on a piece of paper and throw it in the trash and then you have let it go..

Ok, here are a few pointers for you:

1) Try taking some socializing activities like drama classes.
2) Take up a hobby, a part time job, volunteer work. You'll be interacting with different people and you'll probably make new friends which will definitely force you to open up and be brave.
3) Recognise your faults and accept them.
4) Don't speak negatively of yourself. It will only cause more damage.
5)You can also fake it. Just smile and act confident. Think positively
6) Hang out with people that encourage you not bring you down and speak badly of you

But it's not like I'm anti-social or anything.
its just weird because I keep everything in, and I don't
share with anyone.
Does this mean I don't trust people =l

Thanks Icecold.
That's something I'll look into!