Just as my left lung has partially collapsed, my ass collapsed. I'm serious. For some reason, the right side of my ass seems to have deflated or something, so that I'm constantly tugging my underwear out of it. And my underwear used to fit just fine.
I have pneumonia (also) but managed to be in the hospital for only one night! Woo hoo! That was a mistake! If you have pneumonia, stay in the hospital until you start to feel better, no matter what your underwear is doing!