[Merlin tilts his head, because he notices that little recoil, and he wonders about it. It's sort of fascinating in that 'poke a beehive with a stick to see what will happen' sort of way. But even he realizes that it's something to be explored later.]

I'll cast a protection spell to shield us.

[Us, because Merlin is reaching for Arthur's arm now. His ankle has started to swell, and while that does dull the pain, it also makes Merlin feel less sure on his feet.]

Were you going deeper in?

[Because it hasn't occurred to him that Arthur was looking for him.]

Maybe he can pick up the scent. Should I let him off the leash?