It's hard to feel withered when the one giving the look is in such pathetic shape. And Anakin's used to it, anyway. "You can take them or I can stuff them down your throat, Obi-Wan. It's for your own good."

As if he was going to get into a proper healing meditation in this state, anyway. Please.

The description combined with Obi-Wan's not actually remembering what happened just has Anakin wrinkling his nose, "sounds like a very hot shower is called for next."