I have been getting bites mostly on my feet and ankles for a few weeks now, with the odd one on my chest & arms. Initially thought it was from my work office, or from midges however starting to get worried its bed bugs. No sign of fleas and no one else in the house is getting any. I've been washing all the bedding on a hot wash & hoovering my bed and haven't seen any signs up until today when I seen this under my mattress. Is it a bed bug shell?