I did the other way round. After 5 years in Tesco warehouse somewhere in the UK, I went back to Poland to learn web development. Picking jobs are cruel, I'd advise anyone against taking it and trying hardest they can to avoid it. It gives you problems with your back, your legs, gets you bored about life. You get back home physically tired and mentally numb each freaking day, that's because you wear your arse out there forced to ignore any safety rules just to get on time with all tasks and you still get some angry manager calling you every now and then because his managers always push him to achieve more 'picks/hour'. If you see warehouse job ad - run.