I'm a failure, late 20s, never lasted in a job for more than a year. I tried switching careers and went back to school. My new career is in web dev and I started a new job a few months ago. Unfortunately, I am at that stage in which it has become overwhelming and I feel like quitting, again. Not knowing what workload to expect or how long something will take me to fix is stressing me out too much that I am starting to dread waking up. I deal directly with the client and they just expect to fix and finish everything they tell you to do without much help (the company I work at is pretty much an outsourcing IT firm so they don't provide any help at all and you are on your own). For my peace of mind I need something more predictable, does anyone have any advice for a mediocre person with no passions or hobbies? Most of my free time I spend it worrying about stuff. I used to have high grades but unfortunately, that didn't make me a competent person. I do not longer seek gratification or validation from a job. Just something that makes me earn enough money to survive. I'm frugal and besides basic necessities, I don't spend anything more. 

I'm from a developing country so some options might not be available but I appreciate any advice