Why was the blondes belly button bruised? Her boyfriend is blonde. Full text

A brunette goes to see the doctor. "What's the trouble?" he asks her. She tells him, "Everywhere I touch it hurts." "Show me," the doctor says. She touches her elbow and says "Ouch", she touches her knee and says "Ouch", she touches her head and says "Ouch! See Doctor! Everywhere I touch, it hurts!" The doctor says, "You're not really a brunette are you?" She says, surprised, "Why no! I'm really a blonde. Why?" He tells her, "Because your finger is broken". Full text