I really do feel for you as I have suffered in this category, with low self esteem and have gone from one job to another feeling inadequate in them. I dont know there was always something saying, your not doing you job properly and everyone is laughing at you, so I would put my notice in or just leave. The job I am in now is with older people and I truely believe each day I go, I am learning and growing in more ways than I know, so all I can say to you is find something that you dont feel self concious about and you get a passion for, and just do the best you can. One of my customers always used to say this quote to me " I'm no better than anyone else and they are no better than me", and by the way he was 99 years of age, so hearing this I put into action and I quote it daily to myself and I find it helps, hope you find your way soon....