When I 6R, I don’t notice any tension in my head. What do I do?
The tension is there, but you may not be able to feel it yet. It can be quite subtle. Later you will start to recognize it, so just Release and Relax, even if you don’t really feel something.
Since your attention was drawn away from the meditation, you can be sure there was actually tension there. If there was no tension, you would not have been distracted.