HA!
Cotton balls!
Thats weirder than my Balloon thing!
I believe its just the "Ebbe Jeebies". Most people get it with fingers on a chalkboard, and such. It probably has to do with the reaction between rough objects. Your skin is obviously rough with all the fingerprints.
To be honsest, I get it when eating certain foods. Its the consistancy that really causes it. When something rubs against something, it creates a "noise". Rough against rough usually makes a wierd sound, probably mentally undetected by the ears, but physically detected by the censory crap in your fingers, and subconciously taken in through your ears. These together create discomfort in the brain, cause what we call the "Ebie Jeebies", or "Freaking out".
Many things can cause this odd reaction, but it is usually seen with "Rough on Rough". I guess the wool and cotton balls being pulled apart has a similar affect on you as fingers on a chalkboard has to the average person. I actually have learned to accept this feeling. In fact, it really doesn't affect me anymore since tried to "get it" so many times (Fingers on chalkboard). I finally grew adapt to it, and it no longer bothers me.
My advice to you, start pulling apart those cotton balls apart by the hundreds. Accept the feeling, don't fight it. While you do this, your back may "constrict". Its pretty much the spinal coard trying to "Take in" this feeling. Don't worry, everything is fine. It really has no harsh physical affect on you.
Goodluck wit ya cotten