Engineering is a profession and a title, separately or together. You can graduate with a degree in engineering, at which point you can call yourself an engineer no matter what your job is. Or you can have a job with the title "engineer" at which point you can call yourself an engineer for as long as you have that job title. My job title was engineer for a while, then I switched to consulting. When people asked what I did two years ago, I said "I'm an engineer". Now I say "I'm a consultant". It doesn't matter what my degree is.
