People perceive what you are projecting to them. Conscious or unconscious. We as human beings evolve so much that we even don't realise it but people often do. The battle you are feeling is between the past you and the present you.
Your conscious mind try to prove so hard to your unconscious that you feel the struggle very pregnant. To prove that you are shy but, are you anymore?

You said that people don't believe you when you tell to them that you're shy. Why don't YOU believe THEM?

We often try to convince ourselves of different things. Things which might not be true anymore. Things which we passed but are still there.

The idea which you accept, is the reality which you project.
Greetings,
V.