Can you give the definition of "מקצוע"? "Profession" can mean different things to different people. Is it a job that someone who is highly educated has? Is it a career field without respect to education level?
I think מקצוע and "profession" pretty much parallel, also in where they are vague... I imagine English speakers may debate whether house cleaning is a profession; similarly Hebrew speakers may debate whether it is מקצוע, and it will be the exact same debate.