Dan Walker bravely showed off a painful bump on his head to his followers via a selfie on Instagram – following a “completely stupid” injury on Thursday night.The 44 year old sports broadcaster, who is set to take to the stage at the Strictly Come Dancing premiere on Saturday night, ran face-first into a glass door in a cartoonish accident.The collision shocked onlookers from a nearby hotel as they ‘gasped’ when they saw the crash, which left the BBC presenter with a nasty bump above his