Should I strive for a career?

I got a master's degree in engineering, but I don't really care for it. I could probably get a high-paying job in my field, with good career prospects, but it sounds like such a drag. I like working with people, I have a couple of interviews lined up for social work positions, the pay is worse, the work is hard, and the prospects are meager, but still, its more attractive to me.

I do get distracted easily though, I might want to move into a different field in like a year or three and I am afraid no one will hire me because I am not going to stick around. So, to the adults here, should I strive for a career in one field? Do you have experience hopping around different types of work? How did it work out?