The question is unusual. It sounds from the context as though the interviewer wanted to hear about your experience rather than your career. The word experience refers back to what you have gained. The word career refers both to the past and to the future. So it is possible that the interviewer was interested in your vision and ambitions as well. It's hard to know.
Your response might be phrased as:
My experience comprises two years in customer support and three years in sales.
You could make this sound better by saying things like:
My experience comprises two years as a customer support officer and three years as a senior sales representative.
Equally, if the interviewer was interested in your future career, you might say:
In my career so far, I have worked for two years as a customer support officer and three years as a (senior) sales representative. I am currently studying for x degree/qualification with a view to moving into financial management.
I don't see any need to introduce the sentence by referring to two phases/stages/parts. This adds nothing.
It might be worth looking at the reference below regarding the use of comprises and comprised of.