my first job was 11yo, now I have 22, so I tell you properly: the main difficulty is adaptation. Try to have a good relationship with your co-workers, this will make the stress inherent in the work environment lessen and you will feel better.
Bosses tend to be an assholes.
actually Im in the law area and I have been working with this since I was 16, but my first jobs were in a computer company, repairing computers, then I worked with programming too, but before that as a locksmith, cabinetmaker, blacksmith and I worked with painting. In all of these places there were asshole people, but you need to ignore these people, as they will only slow you down and make you feel bad.
Enjoy your work, do your best and enjoy your salary!