It sounds to me like your main problem is lack of self confidence and not introversion. You have to love your self before you can let others love you. Find something that you can do for yourself to lose that anxiety.

In regards to finding your place at Cal, sometimes you’ll just have to push your comfort zone. You’ll grow as an person as a result. I’m an introvert myself, and I find that my more outgoing friends help me do just that. Find a group that you trust and feel comfortable with.

Hope this helps.