Erin,
Red blood cells transport oxygen (basically). How anemic are you? What is your hemoglobin?
You may want to go to a university or Mayo. Sometimes these blood diseases need a 2nd opinion.
A low hemoglobin will make you feel short of breath! Do you know what your O2 is at night? Has someone run a chem panel on you lately, to look at your CO2? What about an arterial blood gas?
Hypoxemia is really hard on the heart, brain, and kidneys. You need someone who really knows their stuff, that doesn't "guess" at what is going on. I mean, come on, can't a hematologist understand the impact of hypoxemia on MG?
No offense. I don't mean to belittle your doctor. But this is basic metabolic/biology stuff.
No wonder you are short of breath when your MG seems okay. What else is going on?!
Please, think about seeking out a 2nd opinion.
Annie
Myelodysplastic syndromes - Symptoms and causes - Mayo Clinic
Myelodysplastic syndromes - Diagnosis and treatment - Mayo Clinic
What Are Red Blood Cells? - Health Encyclopedia - University of Rochester Medical Center