Yep, I used to be the same way up until the time I finished year 13. And then I realized how most of my friendships could have been so much more had I spoken up a bit more. Now I just try to join in conversations when I can. I mean, I still can't do it if it's more than 3/4 people, but it's definitely a start. I feel like people only care if you care too much if you yourself do, and then you being uncomfortable also makes them uncomfortable.