This was my response to someone who sent me a very long email asking "how will I know if I'll like being an architect? Will I like architecture school?" Do you think my response was good, bad, or mean? Here it is:
There is a short answer to this long question - you won't know for certain until you try. Even then, what you do in school rarely reflects what you will do in the real world. There are no sure things and regardless of what your future holds for you, it will require you to take on some sort of risk. What if you wanted to be a pharmacist? How would you know you would like that job?
You can't know, you can only try.