A sinus infection or recurrent infection could be giving you some anxiety symptoms, I had a middle ear infection and i thought i was mad for two weeks.
Its hard being socialable and then losing your confidence, you have to remember that it is there, its just a bit lost right now.
What was it that gave you the confidence in the first place? And why has that changed.
What made you feel good looking, and i bet somewhere along the way you have stopped taking care of yourself.
I asked myself these questions and answered them and do you know what, my confidence is returning slowly.
I used to spend hours styling my hair and I used to by the best make up products, and experiment, but when i got depressed and anxious i stopped.
Since realising that i never pampered myself the way i used to, i started, and boy do i feel better. And I am sure i look better too
Are you having any type of therapy, or discussed this with your dr?
Good luck,