It was not a scratch. It was a passive-aggressive shooting the bird symbol. How do I know it wasn't a scratch? Right now, go to scratch your forehead. To scratch, two or more of your fingers typically curl at the ends to get some nail contact and more power at the fingertips. It's not a block, stress or comfort cue. Those commonly are done with more fingers to cover the face. And notice how very careful he is to not muss his hair. Forming the finger to flip off someone requires effort as does being careful not to mess up your hair and again the little smile when he finishes it says it was worth it to him.
Body Language Expert Patti Wood. For more body language insights go to her website at www.PattiWood.net. Check out Patti's website for her book "SNAP, Making the Most of First Impressions, Body Language and Charisma" at www.snapfirstimpressions.com.