Well... I have the same problem back then during my matriculation years. I have the ideas but I don't know how to say it out loud. It might be my fear of saying those words wrongly or it could be my fear of being laughed by my friends. I cried silently for my fear. But, to my amazement, my friends didn't laugh at me at all. They were so friendly and so nice to me. I learned to speak just by being with them.
During those years, I learned that if we really need to achieve something, we need to try first. Then we have to practice more and more. Friends do play a big role in our life. Five years in the university helped me to 'grow' to be a stronger person - ever!
So... dear students... time will help you along the way. But, you have to try harder than before. Don't ever quit before you try something new in your life. Improving oneself needs a lot of efforts. Don't stop overnight and say that you are not capable of changing yourself for your own sake.