I received both organs at the same time (now 5 months ago) from the same donor. I exercised 5 days a week (aqua aerobics, Yoga, Gym, etc.) and was very active. I never had any breathing issues and now it's only when I exert myself. This started with the transplant. Same as you, when I walk uphill, climb stairs,exercises, etc. it's a trigger. When I bring it up with Doctors (even at the Mayo) they just ignore it. I tapered off Prednisone, however now my white blood cell count is at a critical level (even though I feel great) and they placed me back on 5 mg of Prednisone. I'm still required to do blood work every two weeks - and may have to go back to weekly.
I received a prescription for NEUPOGEN two weeks ago, however my PART D prescription plan is a nightmare attempting to get it approved. I will sign up for a Plan next year (especially since they are doubling the price - I guess hoping that most Seniors will not notice it since they are doing it via the deductible).