Possible Clues:

• One of a pair gets only half a stab of pain
• Slight pain (of conscience?)
• Slight pang, maybe of conscience
• Leyton Orient winger's internal darting pain
• One of the pair will start to have it in pain
• Brief sudden pain
• Sudden sharp feeling
• Sharp pain (of conscience?)
• Double up, for example, in pain
• Lookalike finally suffering unwelcome stabbing pain