Have you thought about seeking a professional help?
yes but my parents don't think it needs attention and i don't have money for it since i am a teenager and not working yet
Start communicating in smaller groups or with one person at a time. Even when in social situations try to communicate with whomsoever you feel comfortable. start small it will build in you confidence and help to overcome fears. Once it's done you can expand. If you already tried this and it didn't help seek a professional.
we always think people think about us but every one thinks about them mostly