Here's what makes your chances very good, and this is very important because it's really how mmj programs have been able to flourish in every state:
A. Your doctor cannot tell you how severe or debilitating your pain is. Pain is a subjective thing, it cannot be measured. It cannot be proven or disproved. Regardless of the underlying condition that causes the pain, if your doctor hears from you that your living, working, eating, or sleeping are disrupted by the pain you experience, he is obligated to record that information in your medical record. That's all you need.
B. Once you have that medical record documenting that you are in pain serious enough that it is affecting your life, that's all the certifying physician (the "pot doc") needs to recommend marijuana.
C. Nobody... ADHS included... nobody can second-guess that physician's recommendation. The patient-physician relationship is afforded that protection in the U.S.
So your only hurdle really is getting your regular doc to record your condition and symptoms.