Bro, there is virtually no way for anybody to tell what could be causing it on these boards. It may not even be related to the juice, it may be allergies or something like that.
I would make an appointment to see a pulmonoligist for sure, and maybe an appointment to see an allergist after that. You don't need to go through your own doc if he is an asshole, just make an appt on your own and tell the pulmonologist the whole story. They make their living answering these types of questions.