I'm an idiot

So after I put my sweater on at work tonight, my right arm has been itchy. I figure I'm just sensitive tonight, especially since this isn't one of my softest sweaters.That was about 12:30am. I just got back from the bathroom and as I was about to open the door I pulled the sleeve of my sweater down a bit. I felt something odd. Lo and behold I had a dryer sheet in there. It's been in my sweater sleeve while I was wearing the sweater for almost 5 hours. I have no idea how I didn't notice it earlier. *headdesk*