I agree. Consult with a lawyer. Any decent lawyer will be ale to make a case with a doctor's prescription and card. But it sounds like you don't have those yet.

If you don't want to just stop smoking for a year to pass your tests, make sure you test clean until you have a judge (or your lawyer, I guess) tell you it's ok to use medicinally. If you don't get approval first and test dirty, you're screwed. I highly doubt a judge would accept "Well, I talked to my doctor about it and was going to get the card, so I figured it was ok."