I sometimes feel that I'm unwanted here and elsewhere, that my opinions are unneeded and my posts are an intrusion. Feeling like that is common, for me, for you, for every other person here. Even when I act like a foolish, clueless, newbie at a minimum I'm prompting someone else to clarify and possibly articulate their own thoughts. When you post you encourage someone else's growth and your own.
As a group we tend to be shy, diffident. That comes along with not feeling natural in our own skins. These feelings will come and go but try to hold on to the thought that what you say IS valuable for your own growth if nothing else.