Either it's a coincidence, or Joshua somehow found out about a recent knife-to-the-shoulder injury that isn't totally healed. Something Spike is immediately reminded of when he clamps right over it.

Regardless, it's regrettable that he has to grit his teeth to keep from groaning in pain and he can only turn his head to hide his expression.

"I haven't decided." -- If it wasn't obvious already, his voice gives it away. Damn everything.