Why don't you see if you can snug it up a little? Take one of those tissues and shove it right inside, a little bit at a time.
Can you get the whole thing in there? Try to get a little softer, so you'll have more room. Here's a little trick: count doubles aloud. 2, 4, 8, 16... The higher you have to count, the more distracted you'll get from your troubles, and the softer you'll be...
Hmm, I don't know. You seem distracted by a... different pair.
Why don't you just keep counting on shoving them in there until you're absolutely sure you can't fit anymore. Keep it nice and warm and tight...