Is there a downside to trying, outside of the fear of failure thing?
It's always a little concerning when you end up combining your career with your relationship, because that adds a whole new level of anxiety, but can you study for this level thingie while staying in your current job?
Can you do it? Absolutely. The question is whether you really want to or whether you'd be doing it just to make your BF happy? If you in your heart of hearts know you'd hate the work itself...