Well first of all don't think of yourself as an "antisocial" person. You obviously want to have positive interactions with people, so that doesn't make you an antisocial person, it's just shyness that gets in the way. When you say you can't fulfill that urge to be loud and the center of attention, that's perfectly common, I think most people are the same way, and it's even a nice quality people appreciate.
So you're not antisocial, you're just shy, there's a difference, and shyness can be overcome. It just takes practice, and yes, there will be mistakes and moments where you feel like you make a complete fool of yourself, but you build off of these experiences and improve yourself.