If you are not delusional you could do some cognitive behavioral therapy to conteract those thoughts. The Feeling Good Handbook by Dr. David Burn is a good start but if you can afford it I would go see a therapist. They can help guide you through the root cause of these thoughts and help you to see different ways around them.
I think maybe you feel insecure?You worry about what people think of you? I dont think youre delusional as you realise these are thoughts that arent true perse.Maybe you could see a counsellor and work on your self esteem