Hi Tyson,
I can understand that you need a break from your mom and want to get away but at what cost to your physical health? I, personally, wouldn't cancel the IVIG. Holding it off for a week can really make a difference with MG. A difference that could swing on the bad side. I've moved my IVIG's up before but never back. How long have you been coughing up green phlegm with blood?
Please make the decision based on your health not on your emotions.
Loving Hugs
Shari