If you see your past and it irritates you, it means you are going to change. Shyness, not being so social, few or maybe less than few friends.. All these factors describe me. I was like this. Today, I am too like this but a bit more confident. And I don't regret it now because I have learnt that the world will judge you at every point of time. Just stay like that what makes you happy. And when you'll feel like this, you are changed :)
I am not changed, my way of thinking is changed. The way I tackle society and everyone is now different. Whats wrong in it if I am not social, or I don't want a larger than life friend circle. I am happy with my one or two close friends that's it. Why I need more fake people in my life if I know I am too sensitive to deal with fake people and show-off and stuff like that. Its me and I am happy. And if you feel that at some point of time you want to change a habit of you only because you want it.. Change it! :)
If you are a happy about yourself, you are far better than others.
Good Luck :)