Congratulations on getting a job. In the world today, it is an extremely massive achievement. Important thing is to stick at the job. If you feel like quiting, look back to what it was like before. After about three months to a year, you will notice a new you. A more confident and motivated you. Perhaps a more healthier you. All good things come in time. Now you have a job, you can tend to that seed and then reap in the harvest
Don't quit your job even if it turns out to be crap. Better wipe the blood sweat and tears than not to give something back to society. It is now easier to get another job whilst in a job. If you don't like this job, you can soon apply for other jobs. Confidence will grow in you with time. Additional: Now you will have some money for yourself to go and have some enjoyment in life, redecorate your kitchen, by a new lightbulb or maybe treat your mates to a lunch at the pub.
Congrats! Hope you enjoy it I recently got a new job too, working with toddlers rather than older kids. More mess but more fun. Anyway well done to you!